Certified Semi-annual Shareholder Report for Management Investment Companies (n-csrs)

ITEM 1. REPORTS TO STOCKHOLDERS.

Closed-End Funds

31 January 2020

Nuveen

Closed-End Funds

Beginning on January 1, 2021, as permitted by regulations adopted by the Securities and Exchange Commission, paper copies of the Funds’ annual and semi-annual shareholder reports will no longer be sent by mail, unless you specifically request paper copies of the reports. Instead, the reports will be made available on the Funds’ website (www.nuveen.com), and you will be notified by mail each time a report is posted and provided with a website link to access the report.

If you have already elected to receive shareholder reports electronically, you will not be affected by this change and you need not take any action. You may elect to receive shareholder reports and other communications from the Funds electronically anytime by contacting the financial intermediary (such as a broker-dealer or bank) through which you hold your Fund shares or, if you are a direct investor, by enrolling at www.nuveen.com/e-reports.

You may elect to receive all future shareholder reports in paper free of charge at any time by contacting your financial intermediary or, if you are a direct investor, (i) by calling 800-257-8787 and selecting option #2 or (ii) by logging into your Investor Center account at www.computershare.com/investor and clicking on “Communication Preferences.” Your election to receive reports in paper will apply to all funds held in your account with your financial intermediary or, if you are a direct investor, to all your directly held Nuveen Funds and any other directly held funds within the same group of related investment companies.

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Table of Contents

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Chair’s Letter to Shareholders

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Portfolio Managers’ Comments

Nuveen Senior Income Fund (NSL)

Nuveen Floating Rate Income Fund (JFR)

Nuveen Floating Rate Income Opportunity Fund (JRO)

Nuveen Short Duration Credit Opportunities Fund (JSD)

Nuveen Credit Strategies Income Fund (JQC)

The Funds’ investment portfolios are managed by Symphony Asset Management, LLC (Symphony), an affiliate of Nuveen Fund Advisors, LLC, the Funds’ investment adviser. During the reporting period, Scott Caraher and Jenny Rhee managed NSL, JFR JRO and JSD, while Scott Caraher, Jenny Rhee and Bernard Wong, CFA, managed JQC.

Effective September 3, 2019, Bernard Wong, CFA, was added as portfolio manager to JQC and Sutanto Widjaja is no longer a portfolio manager on JQC.

Here the team discusses their management strategies and the performance of the Funds for the six-month reporting period ended January 31, 2020.

What strategies were used to manage the Funds during the six-month reporting period ended January 31, 2020?

NSL seeks to achieve a high level of current income, consistent with capital preservation by investing primarily in adjustable rate U.S dollar-denominated secured senior loans. The Fund invests at least 80% of its managed assets in adjustable rate senior secured loans. Up to 20% may include U.S. dollar denominated senior loans of non-U.S. borrowers, senior loans that are not secured, other debt securities and equity securities and warrants. The Fund uses leverage.

JFR seeks to achieve a high level of current income by investing in adjustable rate secured and unsecured senior loans and other debt instruments. The Fund invests at least 80% of its managed assets in adjustable rate loans, primarily senior loans, though the loans may include unsecured senior loans and secured and unsecured subordinated loans. At least 65% the Fund’s managed assets must include adjustable rate senior loans that are secured by specific collateral. The Fund uses leverage.

JRO seeks to achieve a high level of current income. The Fund invests at least 80% of its managed assets in adjustable rate loans, primarily senior loans, though the loans may include unsecured senior loans and secured and unsecured subordinated loans. At least 65% of the Fund’s managed assets must include adjustable rate senior loans that are secured by specific collateral. The Fund uses leverage.

This material is not intended to be a recommendation or investment advice, does not constitute a solicitation to buy, sell or hold a security or an investment strategy and is not provided in a fiduciary capacity. The information provided does not take into account the specific objectives or circumstances of any particular investor, or suggest any specific course of action. Investment decisions should be made based on an investor’s objectives and circumstances and in consultation with his or her advisors.

Certain statements in this report are forward-looking statements. Discussions of specific investments are for illustration only and are not intended as recommendations of individual investments. The forward-looking statements and other views expressed herein are those of the portfolio managers as of the date of this report. Actual future results or occurrences may differ significantly from those anticipated in any forward-looking statements and the views expressed herein are subject to change at any time, due to numerous market and other factors. The Funds disclaim any obligation to update publicly or revise any forward-looking statements or views expressed herein.

For financial reporting purposes, the ratings disclosed are the highest rating given by one of the following national rating agencies: Standard & Poor’s (S&P), Moody’s Investors Service, Inc. (Moody’s) or Fitch, Inc. (Fitch). This treatment of split-rated securities may differ from that used for other purposes, such as for Fund investment policies. Credit ratings are subject to change. AAA, AA, A and BBB are investment grade ratings, while BB, B, CCC, CC, C and D are below investment grade ratings. Holdings designated N/R are not rated by these national rating agencies.

Refer to the Glossary of Terms Used in this Report for further definition of the terms used within this section.

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Portfolio Managers’ Comments (continued)

JSD seeks to provide current income and the potential for capital appreciation. The Fund invests at least 70% of its managed assets in adjustable rate corporate debt instruments, including senior secured loans, second lien loans and other adjustable rate corporate debt instruments, at least 80% of “assets,” at time of purchase, in loans or securities in the issuing company’s capital structure that are senior to its common equity, including but not limited to debt securities, preferred securities and up to 30% of the Fund’s assets may include other types of debt instruments or short positions consisting primarily of high yield debt. The Fund maintains a portfolio with an average duration that does not exceed two years. The Fund uses leverage.

JQC’s primary investment objective is high current income and its secondary objective is total return. The Fund invests at least 70% of its managed assets in adjustable rate senior secured and second lien loans, at least 80% of “assets,” at time of purchase, in loans or securities in the issuing company’s capital structure that are senior to its common equity, including but not limited to debt securities, preferred securities and up to 30% opportunistically in other types of securities across a company’s capital structure, primarily income-oriented securities such as high yield debt, convertible securities and other forms of corporate debt. The Fund uses leverage.

How did the Funds perform during this six-month reporting period ended January 31, 2020?

The tables in the Performance Overview and Holding Summaries section of this report provide total return performance for each Fund for the six-month, one-year, five-year, ten-year and/or since inception periods ended January 31, 2020. The Fund’s total returns at net asset value (NAV) are compared with the performance of a corresponding market index.

The Funds’ total returns at NAV for the reporting period are as follows: NSL 2.65%, JFR 2.69%, JRO 2.68%, JSD 2.06% and JQC 2.84%. Over the same period the Credit Suisse Leveraged Loan Index returned 2.36%.

For the six-month reporting period ending January 31, 2020, U.S. risk assets, including senior loans and high yield bonds, rose on positive and improved investor sentiment as a result of steady U.S. economic growth, accommodative U.S. monetary policy and supportive financial conditions for corporate issuers. During the reporting period, the Credit Suisse Leveraged Loan Index and the ICE BofA High Yield Index returned 2.36% and 3.34%, respectively. These market advances occurred despite periodic spikes in volatility due to the ebb and flow of investor concern toward major macro issues, including but not limited to U.S. and China economic resilience, U.S.-China trade negotiations, U.S.-Iranian tensions and Brexit. Macro anxiety aside, the fundamental environment over the reporting period was conducive to corporate operating conditions, as well as loan and high yield bond returns with the latter only somewhat impacted by retail supply and demand dynamics.

The U.S. economy continued to expand during the reporting period. This reflected strong consumption that was supported by low and modestly declining unemployment, as well as a modest growth in government spending. As reported by the U.S. Bureau of Labor Statistics, U.S. unemployment fell from 3.7% in July 2019 to 3.5% at calendar year-end before rising slightly to 3.6% at period end. Additional workers entering the labor market, a positive factor for the U.S. economy, drove January’s slight increase. The labor force participation rate rose from 63.0% last July 2019 to 63.4% in January 2020, taking it to its highest level since 2013. The increase in the size of labor force allowed the economic expansion to continue without putting excess upward pressure on inflation. Moreover, jobless claims remained at near historically low levels.

Responding to concerns over a potentially slowing U.S. economic growth and macro downside risks, the U.S. Federal Reserve cut its key rate near the beginning of the reporting period and twice again during it. While the rate cuts were widely expected, the Fed’s accommodative stance and resulting lower interest rate environment generally aided corporate financial results by lowering financing costs. In addition, performance of duration credits, such has high yield bonds, was aided by the related decline in U.S. treasury yields. Understanding the positive impact of lower rates on return, investor demand focused on fixed rate over floating rate corporate debt issues. Evidence of this demand bias is the $3.8 billion of inflows into high yield mutual funds in the reporting period versus loan mutual funds that experienced $14.0 billion in withdrawals. Senior loans technicals were also challenging in October 2019 when collateralized loan obligations (CLO) formation slowed. The technical headwind from supply and demand dynamics was one of the drivers for high yield bond outperformance versus senior loans during the reporting period.

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Further lifting investor sentiment were announcements that brought clarity and diminished several geopolitical risks toward the end of the reporting period, most notably, the announcement of the U.S.-China “Phase One” trade deal in December 2019. Investors also received confirmation on the direction of Brexit following the large electoral win by United Kingdom Prime Minister Boris Johnson and breathed a sigh of relief on the de-escalation of U.S.-Iran tensions. Due to these positive macro events, capital market returns were particularly strong in December 2019 and the first half of January 2020. Sentiment, and returns, did peak and trailed downward beginning in the third week of January 2020 on announcements the COVID-19 coronavirus was spreading rapidly. However, this late shift in sentiment and related pullback in performance only modestly offset positive loan and high yield bond returns during the reporting period.

At the end of the reporting period, U.S. economic fundamentals remained generally favorable for U.S. corporate credit. The 1-year default rates for the loan market and high yield bond market ending January 31, 2020 remained low at 2.13% and 2.89%, respectively. Stripping out commodity sectors, the 1-year default rates fell to 1.30% and 1.46%, respectively. Further, although tight relative to historical long-term averages, spreads for senior loans and high yield bonds at the end of the reporting period were 4.58% and 4.74%, respectively; levels that are justified by generally stronger-than-expected corporate results and solid financial conditions.

What other factors impacted Fund Performance?

The senior loan portion of the Funds is invested predominantly in first-lien, senior secured corporate loans. Symphony prefers to focus on issuers that have strong asset coverage, defensible businesses and loans of larger issuance size. These loans are generally referred to as broadly syndicated loans. During the reporting period, the Funds maintained an overall bias towards high quality, more liquid loans. The investment team believed that while credit fundamentals remained sound, the binary outcome of major macro events (U.S.-China trade, Brexit, etc.) increased the potential for downside volatility in the loan market.

The Funds also invest in high yield corporate bonds. High yield bonds are typically invested in opportunistically as Symphony sees value in these assets. Many of the same issuers of high yield bonds also have senior loans outstanding and in some cases, Symphony believes that the bonds of these issuers offer a better risk-return trade-off versus the loans. Oftentimes, Symphony will invest in both the loans and the bonds of the same issuer.

The major allocation and security selection performance factors were similar in NSL, JFR, JRO and JSD. During the reporting period, an overweight exposure to BBB rated loans contributed to performance as these higher quality assets outperformed the overall loan market as measured by the Credit Suisse Leveraged Loan Index. This was particularly the case in third quarter of 2019 as investors’ concerns around macro risks and global growth were elevated. The conservative positioning also allowed the Funds to take on new loan issues at attractive yields during the latter half of the reporting period, when investors were concerned with global macro risks despite a still solid U.S. economy. At the end of the reporting period, the Funds marginally increased exposure to lower credit quality issues.

Also contributing to performance across all the Funds was, in aggregate, issue selection. In the communication services sector, the loans, bonds and re-org equity of iHeart Communications Inc. rose following reports that Liberty Media Corp. reached out to the Department of Justice for permission to acquire a large stake of iHeart. Within the utilities sector, exposure to the credit of PG&E also contributed to absolute and relative performance against the Credit Suisse Leveraged Loan Index. The loans and bonds of PG&E rose on positive investor sentiment as the company remains on track towards exiting bankruptcy, which is targeted for mid-2020. After reaching a settlement with wildfire victims, PG&E reached an agreement with its major debt holders and is expected to reinstate a number of existing loans and bonds. The Fund continues to hold PG&E.

JQC has a differentiated mandate relative to the other Funds. JQC generally has a higher allocation towards the high yield market on a relative basis. This relative overweight to high yield bonds benefited the Fund given their general outperformance versus loans during the reporting period. For comparison, the Credit Suisse Leveraged Loan Index returned 2.36% while the high yield bond market (as measured by the ICE BofA High Yield Index) returned 3.34% over the same period. This larger allocation to high yield bonds was a primary factor to JQC’s outperformance versus the other four Funds over the reporting period. Relative to the Credit Suisse Leveraged Loan Index, JQC’s overweight exposure to BBB rated loans contributed to performance during the reporting period as these higher quality assets outperformed the overall loan market. From a sector perspective, JQC benefited from an overweight in health care, as

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Portfolio Managers’ Comments (continued)

well as strong issuer selection within the sector. Specifically, loans of Tenet Healthcare Corp rose following an above-consensus earnings report. Also contributing to performance were good issue selections in aggregate. Similar to the other four Funds, a top issuer contributing to JQC’s outperformance during the reporting period included iHeart Communications.

From an asset type perspective, while the Funds (NSL, JFR, JRO and JSD) benefited from exposure to high yield bonds, the benefit was more than offset by disappointing issue selections. Specifically, bonds of Intelsat, a satellite services company, detracted from performance. Investors reacted negatively to news the issuer would not benefit to the degree expected from a long awaited auction of its C-band Spectrum that will be used in the development of 5G wireless networks in the U.S. Within the energy sector, the loans of Fieldwood Energy LLC declined during the reporting period, driven primarily by technical headwinds from a large asset manager reducing exposure to the name. The loans of California Resources Corporation also moved lower during the reporting period on rumors and concerns the company would not complete its highly anticipated asset sales and as a result may considering filing for bankruptcy. The Funds continued to hold position in these issuers.

Top detractors for JQC were the same as the other four Funds. However, JQC’s exposure to Intelsat bonds was modestly less.

During the reporting period, JSD underperformed the other four Funds and the Credit Suisse Leveraged Loan Index. The underperformance primarily reflected higher exposure to the relatively weaker energy sector relative to the other Funds.

JSD continued to invest in credit default swaps, which were used to provide a benefit if particular bonds’ credit quality worsened. During the reporting period these credit default swaps had a negligible impact on overall Fund performance.

The elimination of the London Inter-Bank Offered Rate (“LIBOR”) may adversely affect the interest rates on, and value of, certain investments for which the value is tied to LIBOR. The U.K. Financial Conduct Authority has announced that it intends to stop compelling or inducing banks to submit LIBOR rates after 2021. However, it remains unclear if LIBOR will continue to exist in its current, or a modified, form. Alternatives to LIBOR are established or in development in most major currencies, including the Secured Overnight Financing Rate (“SOFR”), which is intended to replace U.S. dollar LIBOR. Markets are slowly developing in response to these new rates. Questions around liquidity impacted by these rates, and how to appropriately adjust these rates at the time of transition, remain a concern. Accordingly, it is difficult to predict the full impact of the transition away from LIBOR until new reference rates and fallbacks for both legacy and new products, instruments and contracts are commercially accepted.

An Update on COVID-19 Coronavirus

The COVID-19 coronavirus pandemic has delivered an exogenous shock to the global economy. Containment efforts around the world have halted business and manufacturing operations and restricted people’s movement and travel. The disruptions to global supply chains, consumer demand, business investment and the global financial system are just beginning to be seen.

Although the virus was detected in China as early as December 2019, markets didn’t fully acknowledge the risks until February 2020, when large outbreaks were reported outside of China. Global stock markets sold off severely, reaching a bear market (a 20% drop from the previous high) within three weeks, the fastest bear market decline in history. Demand for safe-haven assets, along with mounting recession fears, drove the yield on the 10-year U.S. Treasury note below 1% in March, an all-time low. Additionally, oil prices collapsed to an 18-year low in March on supply glut concerns, as shutdowns across the global economy curb oil demand while Saudi Arabia and Russia are flooding the market with cheap oil in a price war.

Central banks and governments have responded with liquidity injections to ease the strain on financial systems and stimulus measures to buffer the shock to businesses and consumers. But markets will likely remain volatile until the health crisis itself is under control (via fewer new cases, slower spread and/or verified treatments). There are still many unknowns and new information is incoming daily, compounding the difficulty of modeling outcomes for epidemiologists and economists alike.

Nuveen is monitoring the situation carefully and continuously refining our views. Our portfolio management teams remain attuned to opportunities to seek risk-adjusted returns through all market environments.

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Fund Leverage

IMPACT OF THE FUNDS’ LEVERAGE STRATEGIES ON PERFORMANCE

One important factor impacting the returns of the Funds’ common shares relative to their cmparitive benchmarks was the Funds’ use of leverage through bank borrowings, Term Preferred Shares (Term Preferred) for NSL, JFR and JRO, Taxable Fund Preferred Shares (TFP) for JSD and reverse repurchase agreements for JQC. The Funds use leverage because our research has shown that, over time, leverageing provides opportunities for additional income. The opportunity arises when short-term rates that a Fund pays on its leveraging instruments are lower than the interest the Fund earns on its portfolio securities that it has bought with the proceeds of that leverage. This has been particularly true in the recent market environment where short-term rates have been low by historical standards.

However, use of leverage can expose Fund common shares to additional price volatility. When a Fund uses leverage, the Fund’s common shares will experience a greater increase in their net asset value if the securities acquired through the use of leverage increase in value, but will also experience a correspondingly larger decline in their net asset value if the securities acquired through leverage decline in value, which will make the shares’ net asset value more volatile, and total return performance more variable, over time.

In addition, common share income in levered funds will typically decrease in comparison to unlevered funds when shortterm interest rates increase and increase when short-term interest rates decrease. In recent quarters, fund leverage expenses have generally tracked the overall movement of short-term tax-exempt interest rates. While fund leverage expenses are somewhat higher than their all-time lows after the 2007-2009 financial crisis, which has contributed to a reduction in common share net income and long-term total return potential, leverage nevertheless continues to provide the opportunity for incremental common share income. Management believes that the potential benefits from leverage continue to outweigh the associated increase in risk and volatility previously described.

The Funds’ use of leverage had a positive impact on total return performance during this reporting period. Subsequent to the close of the reporting period, the outbreak of the COVID-19 pandemic led to a significant downturn in global economies and capital markets. As security prices fell, each Fund’s use of leverage impacted total returns negatively. In response, the Funds have been taking steps to reduce risk by paying down leverage levels pursuant to their leverage risk management protocols, as summarized in “The Funds’ Leverage” section below.

During the current fiscal period, NSL, JFR and JRO used cancellable interest rate swaps in which each Fund received payments based upon pre-determined fixed rates and paid one-month LIBOR plus a fixed spread. After a non-callable period, the swap counterparty owns the right on future monthly dates to terminate the swap at par. The purpose of the cancellable interest rate swap is to convert a fixed rate Term Preferred Share issuance to floating rate, and the cancellation dates of the swap correspond to dates on which the Funds can call the Term Preferred Share issue. Collectively, these interest rate swap contracts had a negligible impact on the Funds’ total return performance during the period.

As of January 31, 2020, the Funds’ percentages of leverage are as shown in the accompanying table.

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Refer to Notes to Financial Statements, Note 9 – Fund Leverage, Borrowings and Note 10 – Subsequent Events, Borrowings for further details.

Reverse Repurchase Agreements

As noted previously, in addition to bank borrowings, JQC also used reverse repurchase agreements, in which the Fund sells to a counterparty a security that it holds with a contemporaneous agreement to repurchase the same security at an agreed-upon price and date. The Fund’s transactions in reverse repurchase agreements are as shown in the accompanying table. Sales reflect on-going leverage management activity that seeks to maintain the Fund’s leverage ratio within a specified internal operating range.

Refer to Notes to Financial Statements, Note 9 – Fund Leverage, Reverse Repurchase Agreements and Note 10 – Subsequent Events, Reverse Repurchase Agreements for further details.

Refer to Notes to Financial Statements, Note 5 – Fund Shares, Preferred Shares for further details on Term Preferred.

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Refer to Notes to Financial Statements, Note 5 – Fund Shares, Preferred Shares and Note 10 – Subsequent Events, Taxable Fund Preferred Shares for further details on TFP.

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Common Share Information

NSL, JFR, JRO and JSD COMMON SHARE DISTRIBUTION INFORMATION

The following information regarding NSL’s, JFR’s, JRO’s and JSD’s distributions is current as of January 31, 2020. Each Fund’s distribution levels may vary over time based on each Fund’s investment activity and portfolio investment value changes.

During the current reporting period, each Fund’s distributions to common shareholders were as shown in the accompanying table.

NSL, JFR, JRO and JSD seek to pay regular monthly dividends out of their net investment income at a rate that reflects their past and projected net income performance. To permit each Fund to maintain a more stable monthly dividend, the Fund may pay dividends at a rate that may be more or less than the amount of net income actually earned by the Fund during the period. Distributions to shareholders are determined on a tax basis, which may differ from amounts recorded in the accounting records. In instances where the monthly dividend exceeds the earned net investment income, the Fund would report a negative undistributed net ordinary income. Refer to Note 6 – Income Tax Information for additional information regarding the amounts of undistributed net ordinary income and undistributed net long-term capital gains and the character of the actual distributions paid by the Fund during the period.

All monthly dividends paid by NSL, JFR, JRO and JSD during the current reporting period were paid from net investment income. If a portion of the Fund’s monthly distributions is sourced or comprised of elements other than net investment income, including capital gains and/or a return of capital, shareholders will be notified of those sources. For financial reporting purposes, the per share amounts of each Fund’s distributions for the reporting period are presented in this report’s Financial Highlights. For income tax purposes, distribution information for each Fund as of its most recent tax year end is presented in Note 6 – Income Tax Information within the Notes to Financial Statements of this report.

JQC DISTRIBUTION INFORMATION

The following information regarding JQC’s distributions is current as of January 31, 2020.

JQC has a capital return plan where a supplemental amount is expected to be included in the Fund’s regular monthly distribution. Under this program, the Fund’s regular monthly distribution is expected to include net investment income, return of capital and potentially capital gains for tax purposes.

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The figures in the table below provide an estimate as of January 31, 2020 of the sources (for tax purposes) of the Fund’s distributions. These source estimates include amounts currently estimated to be attributable to realized gains and/or returns of capital. The Fund attributes these non-income sources equally to each regular distribution throughout the fiscal year. The estimated information shown below is for the distributions paid on common shares for all prior months in the current fiscal year. These estimates should not be used for tax reporting purposes, and the distribution sources may differ for financial reporting than for tax reporting. The final determination of the tax characteristics of all distributions paid in 2020 will be made in early 2021 and reported to you on Form 1099-DIV. More details about the tax characteristics of the Fund’s distributions are available on www.nuveen.com/CEFdistributions.

The following table provides information regarding Fund distributions and total return performance over various time periods. This information is intended to help you better understand whether Fund returns for the specified time periods were sufficient to meet Fund distributions.

CHANGE IN METHOD OF PUBLISHING NUVEEN CLOSED-END FUND DISTRIBUTION AMOUNTS

During November 2019, the Nuveen Closed-End Funds discontinued the practice of announcing Fund distribution amounts and timing via press release. Instead, information about the Nuveen Closed-End Funds’ monthly and quarterly periodic distributions to shareholders are posted and can be found on Nuveen’s enhanced closed-end fund resource page, which is at www.nuveen.com/closed-end-fund-distributions, along with other Nuveen closed-end fund product updates. Shareholders can expect regular distribution information to be posted on www.nuveen.com on the first business day of each month. To ensure that our shareholders have timely access to the latest information, a subscribe function can be activated at this link here, or at this web page (www.nuveen.com/en-us/people/about-nuveen/for-the-media).

COMMON SHARE REPURCHASES

During August 2019, the Funds’ Board of Trustees reauthorized an open-market share repurchase program, allowing each Fund to repurchase an aggregate of up to approximately 10% of its outstanding shares.

As of January 31, 2020, and since the inception of the Funds’ repurchase programs, the Funds have cumulatively repurchased and retired their outstanding common shares as shown in the accompanying table.

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Common Share Information (continued)

During the current reporting period, the Funds did not repurchase any of their outstanding common shares.

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Risk Considerations and Investment Policy Updates

Risk Considerations

Fund shares are not guaranteed or endorsed by any bank or other insured depository institution, and are not federally insured by the Federal Deposit Insurance Corporation.

Nuveen Senior Income Fund (NSL)

Investing in closed-end funds involves risk; principal loss is possible. There is no guarantee the Fund’s investment objectives will be achieved. Closed-end fund shares may frequently trade at a discount or premium to their net asset value. Adjustable Rate Senior Loans may not be fully secured by collateral, generally do not trade on exchanges, and are typically issued by unrated or below-investment grade companies, and therefore are subject to greater liquidity and credit risk. Lower credit debt securities may be more likely to fail to make timely interest or principal payments. Leverage increases return volatility and magnifies the Fund’s potential return and its risks; there is no guarantee a fund’s leverage strategy will be successful. These and other risk considerations such as interest rate risk are described in more detail on the Fund’s web page at www.nuveen.com/NSL.

Nuveen Floating Rate Income Fund (JFR)

Investing in closed-end funds involves risk; principal loss is possible. There is no guarantee the Fund’s investment objectives will be achieved. Closed-end fund shares may frequently trade at a discount or premium to their net asset value. Adjustable Rate Senior Loans may not be fully secured by collateral, generally do not trade on exchanges, and are typically issued by unrated or below-investment grade companies, and therefore are subject to greater liquidity and credit risk. Lower credit debt securities may be more likely to fail to make timely interest or principal payments. Leverage increases return volatility and magnifies the Fund’s potential return and its risks; there is no guarantee a fund’s leverage strategy will be successful. These and other risk considerations such as interest rate risk are described in more detail on the Fund’s web page at www.nuveen.com/JFR.

Nuveen Floating Rate Income Opportunity Fund (JRO)

Investing in closed-end funds involves risk; principal loss is possible. There is no guarantee the Fund’s investment objectives will be achieved. Closed-end fund shares may frequently trade at a discount or premium to their net asset value. Adjustable Rate Senior Loans may not be fully secured by collateral, generally do not trade on exchanges, and are typically issued by unrated or below-investment grade companies, and therefore are subject to greater liquidity and credit risk. Lower credit debt securities may be more likely to fail to make timely interest or principal payments. Leverage increases return volatility and magnifies the Fund’s potential return and its risks; there is no guarantee a fund’s leverage strategy will be successful. These and other risk considerations such as interest rate risk are described in more detail on the Fund’s web page at www.nuveen.com/JRO.

Nuveen Short Duration Credit Opportunities Fund (JSD)

Investing in closed-end funds involves risk; principal loss is possible. There is no guarantee the Fund’s investment objectives will be achieved. Closed-end fund shares may frequently trade at a discount or premium to their net asset value. Adjustable Rate Senior Loans may not be fully secured by collateral, generally do not trade on exchanges, and are typically issued by unrated or below-investment grade companies, and therefore are subject to greater liquidity and credit risk. Lower credit debt securities may be more likely to fail to make timely interest or principal payments. Leverage increases return volatility and magnifies the Fund’s potential return and its risks; there is no guarantee a fund’s leverage strategy will be successful. These and other risk considerations such as interest rate risk are described in more detail on the Fund’s web page at www.nuveen.com/JSD.

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Risk Considerations and Investment Policy Updates (continued)

Nuveen Credit Strategies Income Fund (JQC)

Investing in closed-end funds involves risk; principal loss is possible. There is no guarantee the Fund’s investment objectives will be achieved. Closed-end fund shares may frequently trade at a discount or premium to their net asset value. Adjustable Rate Senior Loans may not be fully secured by collateral, generally do not trade on exchanges, and are typically issued by unrated or below-investment grade companies, and therefore are subject to greater liquidity and credit risk. Lower credit debt securities may be more likely to fail to make timely interest or principal payments. Common stock prices have often experienced significant volatility. Leverage increases return volatility and magnifies the Fund’s potential return and its risks; there is no guarantee a fund’s leverage strategy will be successful. These and other risk considerations such as interest rate risk are described in more detail on the Fund’s web page at www.nuveen.com/JQC.

Investment Policy Updates

Change in Investment Policy

Each Fund has recently adopted the following policy regarding limits to investments in illiquid securities:

While there are no such limits imposed by applicable regulations, certain Nuveen Closed-End Funds formerly had investment policies that placed limits on a Fund’s ability to invest in illiquid securities. All exchange-listed Nuveen Closed-End Funds now have no formal limit on their ability to invest in such illiquid securities, but each Fund’s portfolio management team will monitor such investments in the regular, overall management of the Funds’ portfolio securities.

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Refer to Glossary of Terms Used in this Report for further definition of the terms used within this section.

Past performance is not predictive of future results. Current performance may be higher or lower than the data shown. Returns do not reflect the deduction of taxes that shareholders may have to pay on Fund distributions or upon the sale of Fund shares. Returns at NAV are net of Fund expenses, and assume reinvestment of distributions. Comparative index return information is provided for the Fund’s shares at NAV only. Indexes are not available for direct investment.

Common Share Price Performance — Weekly Closing Price

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This data relates to the securities held in the Fund’s portfolio of investments as of the end of the reporting period. It should not be construed as a measure of performance for the Fund itself. Holdings are subject to change.

For financial reporting purposes, the ratings disclosed are the highest rating given by one of the following national rating agencies: Standard & Poor’s Group, Moody’s Investors Service, Inc. or Fitch, Inc. This treatment of split-rated securities may differ from that used for other purposes, such as for Fund investment policies. Credit ratings are subject to change. AAA, AA, A and BBB are investment grade ratings; BB, B, CCC, CC, C and D are below-investment grade ratings. Holdings designated N/R are not rated by these national rating agencies.