Strategy. The Oregon Municipal Bond Portfolio seeks its investment objective by investing primarily in a universe of municipal securities issued by or on behalf of Oregon state or local governments and their agencies, instrumentalities and regional governmental authorities, the interest on which is exempt from regular federal income tax and the state personal income tax of Oregon. Municipal securities in which the Portfolio may invest include, among others, revenue bonds, general obligation bonds, industrial development bonds, municipal lease obligations, commercial paper, variable rate demand obligations and other instruments (including participation interests in such securities). The Portfolio invests in municipal and other fixed income securities that have an investment grade credit rating (e.g., rated AAA to BBB- by S&P Global Ratings (S&P) … Show more… The Oregon Municipal Bond Portfolio seeks its investment objective by investing primarily in a universe of municipal securities issued by or on behalf of Oregon state or local governments and their agencies, instrumentalities and regional governmental authorities, the interest on which is exempt from regular federal income tax and the state personal income tax of Oregon. Municipal securities in which the Portfolio may invest include, among others, revenue bonds, general obligation bonds, industrial development bonds, municipal lease obligations, commercial paper, variable rate demand obligations and other instruments (including participation interests in such securities). The Portfolio invests in municipal and other fixed income securities that have an investment grade credit rating (e.g., rated AAA to BBB- by S&P Global Ratings (S&P) or Fitch Ratings Ltd. (Fitch) or Aaa to Baa3 by Moodys Ratings (Moodys) or an equivalent rating assigned by another nationally recognized statistical rating organization, or that are unrated but have been determined by Dimensional Fund Advisors LP (the Advisor) to be of comparable quality). The Oregon Municipal Bond Portfolio intends to invest in municipal securities that in the opinion of bond counsel for the issuers and under current tax law provide interest that is exempt from Oregon and federal personal income taxes. As a fundamental investment policy, under normal market conditions, the Portfolio will invest at least 80% of its net assets in municipal securities that pay interest exempt from federal personal income tax and the Oregon state personal income tax. The Portfolio does not currently intend to invest its assets in municipal securities whose interest is subject to the federal alternative minimum tax. Generally, the Oregon Municipal Bond Portfolio will acquire obligations that mature within twenty years from the date of settlement, and in variable rate demand obligations with longer maturities. Under normal circumstances, the Portfolio will maintain a weighted average duration of no less than three years and no greater than six years. If a security has been or is expected to be redeemed by the issuer at a date prior to the stated final maturity date for the purposes of the above duration restriction, the early redemption date shall be considered the maturity date regardless of the stated final maturity. If a security's coupon or interest rate is periodically reset, the reset date will be considered for the purposes of the above duration restriction. From time to time, the Portfolio may deviate from this duration range when the Advisor determines it to be appropriate under the circumstances. Duration is a measure of the sensitivity of a securitys price to changes in interest rates. The longer a securitys duration, the more sensitive it will be to changes in interest rates. Municipal securities are often issued to obtain funds for various public purposes, including the construction of a wide range of public facilities, such as bridges, highways, housing, hospitals, mass transportation facilities, schools, streets and public utilities, such as water and sewer works. Municipal securities include municipal leases, certificates of participation, municipal obligation components and municipal custody receipts. The Oregon Municipal Bond Portfolio may invest more than 25% of its assets in municipal securities issued to finance projects in a particular segment of the bond market including, but not limited to, health care, housing, education, utilities, and transportation. The Portfolio also may invest more than 25% of its assets in industrial development bonds. The Oregon Municipal Bond Portfolio may (1) purchase certain municipal securities that are insured, (2) invest in municipal securities secured by mortgages on single-family homes and multi-family projects, (3) invest in pre-refunded municipal securities, (4) purchase tax-exempt municipal securities on a when-issued basis and (5) use derivatives, such as fixed income related futures and options contracts, credit default swaps and interest rate swaps, to hedge against changes in interest rates. The Portfolio may also invest in exchange-traded funds (ETFs) to gain exposure to the municipal bond market pending investment in municipal bonds. The Portfolio may also invest in money market funds. The Portfolio also may purchase or sell futures contracts and options on futures contracts, to hedge its interest rate exposure or for non-hedging purposes, such as a substitute for direct investment or to increase or decrease market exposure based on actual or expected cash inflows to or outflows from the Portfolio. Although the Oregon Municipal Bond Portfolio attempts to invest all of its assets in tax-exempt securities, it is possible, although not anticipated, that a portion of its assets may be invested in securities that pay taxable interest, including interest that may be subject to the federal alternative minimum tax. These investments could generate taxable income for shareholders. The Oregon Municipal Bond Portfolio is primarily designed for investment by Oregon taxpayers. The Oregon Municipal Bond Portfolio is non-diversified, which means that the Portfolio may invest its assets in a smaller number of issuers than a diversified fund. Show less