Strategy. The Fund employs an indexing (or passive) investment approach designed to track the performance of the Index, which is constructed by Harbor Capital Advisors, Inc. (Harbor Capital, the Advisor or the Index Provider) in accordance with a proprietary, rules-based methodology. The Index consists of next generation (generally defined as non-traditional) real estate investment trusts (REITs) traded on U.S. exchanges that exhibit positive fundamental and price characteristics according to the Index Providers methodology. The Fund invests at least 80% of its total assets in securities that are included in the Index. A REIT is an entity dedicated to owning, and usually operating, income-producing real estate, or to financing real estate. REITs pool investors funds for investment primarily in income-producing real estate … Show more… The Fund employs an indexing (or passive) investment approach designed to track the performance of the Index, which is constructed by Harbor Capital Advisors, Inc. (Harbor Capital, the Advisor or the Index Provider) in accordance with a proprietary, rules-based methodology. The Index consists of next generation (generally defined as non-traditional) real estate investment trusts (REITs) traded on U.S. exchanges that exhibit positive fundamental and price characteristics according to the Index Providers methodology. The Fund invests at least 80% of its total assets in securities that are included in the Index. A REIT is an entity dedicated to owning, and usually operating, income-producing real estate, or to financing real estate. REITs pool investors funds for investment primarily in income-producing real estate or real estate-related loans or interests. The Index construction process involves the following steps: The Index Provider identifies the universe of securities eligible to be included in the Index (the Index Universe). The Index Universe consists of all next-generation REITs within the largest 3000 securities listed on U.S. exchanges subject to certain constraints with respect to size, liquidity, price and sales. The Index Provider generally defines next-generation REITs as those within the following RBICS (Factsets Revere Business Industry Classification System) sub-industry classifications: data center equity REITs, gaming equity REITs, healthcare and life sciences equity REITs, hotel and motel equity REITs, land equity REITs, manufactured homes equity REITs, self-storage equity REITs and tower equity REITs. As of December 31, 2024, the Index Universe consisted of 58 companies. The Index Provider then scores each company in the Index Universe based on its proprietary stock selection scoring model, which assesses companies across five individual factor composites: Capital Deployment, Momentum, Quality, Risk and Valuation. Each individual factor composite reflects a combination of various factors or metrics. The individual factor composites are combined to produce an overall stock selection score. The weighting of the individual factor composites to produce a securitys overall score is determined in accordance with the Index Providers regime model, which is used to determine the prevailing business cycle regime. The business cycle regime is used to identify the current environment for riskier assets by evaluating various economic conditions (e.g. growth, liquidity, inflation, sentiment). Based on the stock selection scores determined above, the Index Provider uses an optimization engine to maximize the expected information ratio relative to a market capitalization-weighted reference portfolio of non-traditional REITs. Portfolio optimization is the process of selecting and weighting an optimal portfolio from a set of possible portfolios in accordance with a set objective, in this case to maximize the information ratio relative to the reference portfolio, subject to certain constraints. The information ratio is a measure of risk-adjusted returns of a portfolio relative to a benchmark, with a higher information ratio indicating better risk-adjusted returns. The Index typically includes between 35 and 70 constituent REITs. At the time of reconstitution, the hotel and motel equity REITs sub-industry is capped at 15% of the Index. As of December 31 2024, the Index consisted of 37 securities. The Index has been created by Harbor Capital and is calculated, published and distributed by Solactive AG (Solactive). The Index is normally reconstituted and rebalanced monthly. The components of the Index, the number of components and the degree to which these components represent certain industries, or groups of industries may change over time. The Fund will concentrate its investments in a particular industry or group of industries from time to time to approximately the same extent that the Index concentrates in an industry or group of industries. As of the date of this Prospectus, the Index is concentrated in the group of industries comprising the real estate sector. The Fund uses an indexing investment approach to attempt to approximate, before fees and expenses, the investment performance of the Index. The Fund generally will use a replication strategy, which means that the Fund seeks to hold each security found in the Index in approximately the same proportion as represented in the Index itself. However, the Fund may under certain circumstances use a representative sampling strategy, which means the Fund would invest in a representative sample of securities with an investment profile, collectively, similar to that of the Index. The Fund does not take temporary defensive positions when markets decline or appear overvalued. The Fund may also invest in cash and cash equivalents, including shares of money market funds. The Fund is classified as non-diversified, which means the Fund may invest in the securities of a smaller number of issuers than a diversified fund. Show less