Strategy. Under normal circumstances, the Fund invests at least 40% of its net assets, plus any borrowings for investment purposes, in securities of foreign companies. The Fund invests in securities regardless of market capitalization size (small, medium or large). For security selection and portfolio construction, Principal Global Investors, LLC ("PGI") uses a proprietary quantitative model. The model is designed to identify and rank equity securities in the MSCI World Ex-U.S. Index (the "Index") that correspond to factor categories including the following: Value companies securities with low prices relative to their fundamental value, measured by such metrics as earnings yield, free cash flow yield, and sales yield. Higher quality companies securities ranked based on metrics such as return on equity, sales growth, … Show more… Under normal circumstances, the Fund invests at least 40% of its net assets, plus any borrowings for investment purposes, in securities of foreign companies. The Fund invests in securities regardless of market capitalization size (small, medium or large). For security selection and portfolio construction, Principal Global Investors, LLC ("PGI") uses a proprietary quantitative model. The model is designed to identify and rank equity securities in the MSCI World Ex-U.S. Index (the "Index") that correspond to factor categories including the following: Value companies securities with low prices relative to their fundamental value, measured by such metrics as earnings yield, free cash flow yield, and sales yield. Higher quality companies securities ranked based on metrics such as return on equity, sales growth, earnings growth, and balance sheet measures of quality (such as lower debt and accruals). Higher momentum companies securities ranked by evaluating recent performance. Lower volatility companies identified using the recent standard deviation of returns (in other words, how much such returns vary). The model incorporates a proprietary rules-based methodology that identifies the current market risk regime as "lower," "higher and increasing," or "higher and decreasing" and then weights securities within and among the factor categories based on the prevailing market regime. During "higher and decreasing" market risk environments, the model is expected to correspond more closely to the weights used in the Index itself; however, in other regimes, the models selection and weighting is expected to differ from the Index in an effort to outperform the Index returns after fees and expenses. In "lower" risk environments, the model is expected to allocate more to value, quality, and momentum stocks, while de-emphasizing lower volatility stocks, whereas in "higher and increasing" risk environments the model is expected to allocate more to lower volatility stocks, as well as quality and momentum stocks, while de-emphasizing value stocks. For certain securities, the model assigns weights equal to that of the Index in all risk regimes. PGI expects to review the risk environment weekly. In circumstances where the risk environment does not change, the Fund's holdings are expected to be rebalanced semi-annually. Fund holdings will be rebalanced more frequently in the event of market risk regime shifts, which will result in increased portfolio turnover. PGI expects to review the model and risk environment regularly, and adjustments to the model and Fund holdings may be made at PGI's discretion. The Funds strategies may result in the active and frequent trading of the Funds portfolio securities. Note: "MSCI" is a trademark of MSCI Inc. and has been licensed by Principal. The Fund is not sponsored, endorsed, sold, or promoted by MSCI, and MSCI makes no representation regarding the advisability of investing in the Fund. Show less