Pricing & Performance

Footnotes

¹ Small-cap and mid-cap investment options are subject to more fluctuation in value and may have additional risks than other investment options with stocks of larger, more stable companies.

² Each index based investment option is invested in the stocks or bonds of the index it tracks. Performance of indexes reflects the unmanaged results for the market segment the selected stocks or bonds represent. There is no assurance an index based investment option will match the performance of the index tracked.

³ International and global investment options are subject to additional risk due to fluctuating exchange rates, foreign accounting and financial policies, and other economic and political environments.

⁴ High yield investment options are subject to greater credit risk and volatility that is associated with high yield bonds.

⁵ Real Estate investment options are subject to investment and liquidity risk and other risks inherent in real estate such as those associated with general and local economic conditions. Property values can decline due to environmental and other reasons. In addition, fluctuation in interest rates can negatively impact the performance of real estate investment options.

⁶ An investment in the Fund is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. You could lose money by investing in the Fund. Although the Fund seeks to preserve the value of your investment at $1.00 per share, it cannot guarantee it will do so. The Fund's sponsor has no legal obligation to provide financial support to the Fund, and you should not expect that the sponsor will provide financial support to the Fund at any time.

⁷ S&P 500 is a trademark of S&P Global and is used under license. The product is not sponsored, endorsed, sold or promoted by Standard & Poor's and Standard & Poor's makes no representation regarding the advisability of investing in the product.

¹¹ These calculated returns reflect the historical performance of the oldest share class of the fund, adjusted to reflect a portion of the fees and expenses of this share class. For time periods prior to inception date of the fund, predecessor performance is reflected. Please see the fund's prospectus for more information on specific expenses, and the fund's most recent shareholder report for actual date of first sale. Expenses are deducted from income earned by the fund. As a result, dividends and investment results will differ for each share class.

¹² Equity investment options involve greater risk, including heightened volatility, than fixed-income investment options. Fixed-income investment options are subject to interest rate risk, and their value will decline as interest rates rise.

¹³ Asset allocation does not guarantee a profit or protect against a loss. Investing in real estate, small-cap, international, and high-yield investment options involves additional risks.

¹⁴ Fixed-income investment options are subject to interest rate risk, and their value will decline as interest rates rise. A portion of the Fund's income may be subject to state and/or local taxes, and it may be subject to federal alternative minimum tax (AMT) for certain investors.

¹⁵ Small-cap and mid-cap stocks may have additional risks, including greater price volatility.

¹⁶ Fixed-income investment options are subject to interest rate risk, and their value will decline as interest rates rise. Neither the principal of bond investment options nor their yields are guaranteed by the U.S. government.

¹⁸ Fixed-income and asset allocation investment options that invest in mortgage securities are subject to increased risk due to real estate exposure.

¹⁹ Instances of high double-digit returns were achieved primarily during favorable market conditions and may not be sustainable over time.

²⁰ Fixed-income investment options are subject to interest rate risk, and their value will decline as interest rates rise. Lower-rated securities are subject to additional credit and default risks. Risks associated with preferred securities differ from risks inherent with other investments. In particular, in the event of bankruptcy, a company's preferred securities are senior to common stock but subordinated to all other types of corporate debt. International investing involves increased risks due to currency fluctuations, political or social instability, and differences in accounting standards, these risks are magnified in emerging markets. REIT securities are subject to risk factors associated with the real estate industry and tax factors of REIT registration.

²¹ The investment adviser may voluntarily limit a certain portion of the fund's expenses collected from the Money Market Fund on a temporary basis.

²² The manager of the Fund, Principal Global Investors, invests between 10% and 40% of the Fund's assets in common stocks in an attempt to match or exceed the performance of the Fund's benchmark index for performance.

²³ Asset allocation and diversification do not ensure a profit or protect against a loss. Additionally there is no guarantee this investment option will provide adequate income at or through retirement.

²⁴ Fixed-income investment options are subject to interest rate risk, and their value will decline as interest rates rise. Neither the principal of bond investment options nor their yields are guaranteed by the U.S. or any other government entity. Concentrating investments in natural resources industries can be affected significantly by events relating to those industries, such as variations in the commodities markets, weather, disease, embargoes, international, political and economic developments, the success of exploration projects, tax and other government regulations and other factors. Investment in derivatives entails specific risks relating to liquidity, leverage and credit that may reduce returns and/or increase volatility. REIT securities are subject to risk factors associated with the real estate industry and tax factors of REIT registration. An MLP that invests in a particular industry (e.g., oil and gas) may be harmed by detrimental economic events within that industry. As partnerships, MLPs may be subject to less regulation (and less protection for investors) under state laws than corporations. In addition, MLPs may be subject to state taxation in certain jurisdictions, which may reduce the amount of income paid by an MLP to its investors.

³¹ For Government High Quality Bond Fund (A) the Distributor has voluntarily agreed to waive .10% which limits the investment option's 12b-1 fees to .15%. These limits apply now but may be terminated at any time.

³² This fund utilizes alternative investment strategies such as arbitrage, leverage, derivatives, and shorting securities in addition to traditional investments. Investment risk may be magnified with the use of these alternative strategies. In addition, securities such as bonds, equities, commodities, international and emerging market securities, and currencies are used to implement the investment strategy. These investments are subject to risks associated with market and interest rate movements. The fund is considered non-diversified which may make it more susceptible to price volatility if the fund does not meet its objective. Due to the nature of the investment process, investors should not expect significant outperformance during market rallies. Additional risks are included in the funds prospectus. It is possible to lose money when investing in the fund.

³³ The risks associated with derivative investments include that the underlying security, interest rate, market index, or other financial asset will not move in the direction the Investment Adviser and/or Sub-Advisor anticipated, the possibility that there may be no liquid secondary market, the risk that adverse price movements in an instrument can result in a loss substantially greater than a fund's initial investment, the possibility that the counterparty may fail to perform its obligations; and the inability to close out certain hedged positions to avoid adverse tax consequences.

³⁴ Formerly known as MidCap Blend Fund.

³⁶ Effective June 14, 2013, the Principal MidCap Fund closed to certain new investors. Please see the prospectus for more complete information

⁴² During 2015, the Class experienced a significant withdrawal of monies by an affiliate. As the remaining shareholders held relatively small positions, the total return amounts expressed herein are greater than those that would have been experienced without the withdrawal.

⁴³ International and global investing involves greater risks such as currency fluctuations, political/social instability and differing accounting standards.

⁴⁴ Formerly known as SmallCap Blend Fund.

⁴⁵ Formerly known as Bond & Mortgage Securities Fund.

⁴⁹ During 2016, the Class experienced a significant withdrawal of monies by an affiliate. As the remaining shareholders held relatively small positions, the total return amounts expressed herein are greater than those that would have been experienced without the withdrawal.

⁵¹ You could lose money by investing in the Fund. Although the Fund seeks to preserve the value of your investment at $1.00 per share, it cannot guarantee it will do so. The Fund may impose a fee upon sale of your shares or may temporarily suspend your ability to sell shares if the Fund's liquidity falls below required minimums because of market conditions or other factors. An investment in the Fund is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. The Fund's sponsor has no legal obligation to provide financial support to the Fund, and you should not expect that the sponsor will provide financial support to the Fund at any time.

⁵⁴ Effective December 1, 2016, the Principal Small-MidCap Dividend Income Fund closed to certain new investors. Please see the prospectus for more complete information.

⁵⁶ This Principal LifeTime Fund indirectly bears its pro rata share of the management fees incurred by the underlying Principal Funds in which this fund invests. Based on the asset allocation of the Principal LifeTime Funds outlined in the prospectus dated March 1, 2017, the weighted average operating expenses of the underlying funds are: Principal LifeTime Strategic Income, 0.61%; Principal LifeTime 2010, 0.65%; Principal LifeTime 2020, 0.70%; Principal LifeTime 2030, 0.72%; Principal LifeTime 2040, 0.70%; Principal LifeTime 2050, 0.72%. While the operating expenses of the underlying mutual funds are not part of the Principal LifeTime Fund's operating expenses they are included in the Total Investment Expense. Performance results shown for the Principal LifeTime Fund reflect the application of these expenses.

⁵⁸ This Principal Strategic Asset Management Portfolio (SAM) indirectly bears its pro rata share of the management fees incurred by the underlying Principal Funds in which this portfolio invests. Based on the asset allocation of the SAM Portfolio outlined in the prospectus dated March 1, 2017, the weighted average operating expenses of the underlying funds are: Flexible Income, 0.57%; Conservative Balanced, 0.68%; Balanced, 0.74%; Conservative Growth, 0.79%; Strategic Growth, 0.78%. While the operating expenses of the underlying mutual funds are not part of the SAM Portfolio operating expenses they are included in the Total Investment Expense. Performance results shown for the SAM Portfolios reflect the application of these expenses.

⁶³ Effective October 2, 2017, this portfolio is sub-advised by Neuberger Berman, Mellon and DDJ. Prior to October 2, 2017, the portfolio was sub-advised by JP Morgan and Neuberger Berman. The portfolio has had various sub-advisors since its inception. Performance results displayed reflect all sub-advisors managing this portfolio during the time periods displayed.

⁶⁴ Fixed-income investment options are subject to interest rate risk, and their value will decline as interest rates rise. Risks of preferred securities differ from risks inherent in other investments. In particular, in a bankruptcy preferred securities are senior to common stock but subordinate to other corporate debt. Contingent capital securities (CoCos) may have substantially greater risk than other securities in times of financial stress. An issuer or regulators decision to write down, write off or convert a CoCo may result in complete loss on an investment.

⁶⁶ This Principal LifeTime Fund indirectly bears its pro rata share of the management fees incurred by the underlying Principal Funds in which this fund invests. Based on the asset allocation of the Principal LifeTime Funds outlined in the prospectus dated March 1, 2018, the weighted average operating expenses of the underlying funds are: Principal LifeTime Strategic Income, 0.62%; Principal LifeTime 2010, 0.65%; Principal LifeTime 2020, 0.69%; Principal LifeTime 2030, 0.71%; Principal LifeTime 2040, 0.68%; Principal LifeTime 2050, 0.70%. While the operating expenses of the underlying mutual funds are not part of the Principal LifeTime Fund's operating expenses they are included in the Total Investment Expense. Performance results shown for the Principal LifeTime Fund reflect the application of these expenses.

⁶⁸ This Principal Strategic Asset Management Portfolio (SAM) indirectly bears its pro rata share of the management fees incurred by the underlying Principal Funds in which this portfolio invests. Based on the asset allocation of the SAM Portfolio outlined in the prospectus dated March 1, 2018, the weighted average operating expenses of the underlying funds are: Flexible Income, 0.56%; Conservative Balanced, 0.68%; Balanced, 0.75%; Conservative Growth, 0.74%; Strategic Growth, 0.75%. While the operating expenses of the underlying mutual funds are not part of the SAM Portfolio operating expenses they are included in the Total Investment Expense. Performance results shown for the SAM Portfolios reflect the application of these expenses.

⁷⁰ Effective June 29, 2018, this portfolio is sub-advised by Vaughn Nelson, LA Capital and Hotchkis & Wiley. Prior to June 29, 2018, the portfolio was sub-advised by DFA, Vaughn Nelson and LA Capital. The portfolio has had various sub-advisors since its inception. Performance results displayed reflect all sub-advisors managing this portfolio during the time periods displayed.

⁷² Effective November 30, 2018, class C shares will be closed to new investors. Effective January 11, 2019, class C shares will be converted to the respective class A shares.