*The ratio of total assets of the Fund, less all liabilities that are not outstanding borrowings or outstanding preferreds, at par, to the sum of the Fund’s outstanding borrowings and outstanding preferreds, at par.

**The annualized ratio of the sum of leverage costs to the average leverage amount for a given time period.

Adjusted expense ratio excludes leverage financing expenses, including interest expenses and other leverage-related expenses. Nuveen earns a management fee on total investment capital, which includes common assets as well as assets attributable to the Fund’s issuance of senior securities (e.g. preferred shares and debt), that is displayed in Management Fee on Managed Assets.

For Class A1 and Class A2 Common Shares, the Fund has adopted a Distribution and Servicing Plan. The Distribution and Servicing Plan permits the Fund to compensate the Distributor for using reasonable efforts to secure purchasers of the Fund's Common Shares, including by providing continuing information and investment services and/or by making payments to certain authorized institutions in connection with the sale of Common Shares or servicing of shareholder accounts. The maximum annual rates at which the distribution and/or servicing fees may be paid under the Distribution and Servicing Plan (calculated as a percentage of the Fund's average daily net assets attributable to the respective common share classes) is 0.75% for Class A1 and 0.50% for Class A2. Please refer to the prospectus for more information about fees and expenses.

Expense ratios do not include interest expenses arising from the application of SFAS No. 140 to certain inverse floating rate securities (if any) held by the Fund. Interest expense arises because accounting rules require the Fund to treat interest paid by trusts issuing certain inverse floating rate instruments held by the Fund as having been paid (indirectly) by the Fund. Because the Fund also recognizes a corresponding amount of additional income earned (also indirectly), the Fund's net asset value per share, net investment income and total return have not been affected by this accounting treatment. See the Fund's Annual Report for information on the Fund's inverse floating rate investments and recognized interest expense.​

Expense ratios are calculated using the prior 12 months of expense data as of the previous quarter-end. The Fund’s adviser has agreed to waive fees and/or reimburse expenses through July 31, 2026 so that the total annual operating expenses of the Fund (excluding distribution and service fees and certain other expenses) do not exceed 1.05% of the average daily managed assets of any class of Fund shares. See the prospectus for details.

For additional details about the Fund’s ordinary income, see the Fund’s Section 19(a) Notice.

*Daily income: Dividend amount declared daily by the fund. Monthly income: Dividend amount is the sum of all daily dividends in a month. Any re-characterization will be reported in shareholders’ 1099-DIV forms after the end of the year. Ordinary income: Income amount may include both Short-Term Capital Gain and market discount. Market Discount is the excess of the stated redemption price of the bond at maturity over the basis of such bond immediately after its acquisition. Funds are required to recognize Short-Term Capital Gain and market discount as ordinary taxable income.