Strategy. MFS (Massachusetts Financial Services Company, the fund's investment adviser) normally invests at least 80% of the funds net assets in inflation-adjusted debt instruments and other instruments with similar economic characteristics. MFS generally focuses the funds investments in inflation-adjusted debt instruments issued by U.S. and foreign governments. MFS may also invest the funds assets in inflation-adjusted debt instruments of other issuers, other instruments with similar economic characteristics to these instruments, including derivatives, and non-inflation-adjusted debt instruments. MFS primarily invests the funds assets in investment grade quality debt instruments, but may also invest the funds assets in below investment grade quality debt instruments. MFS invests the funds assets in U.S. and foreign securities. MFS normally invests the fund's assets across different countries … Show more… MFS (Massachusetts Financial Services Company, the fund's investment adviser) normally invests at least 80% of the funds net assets in inflation-adjusted debt instruments and other instruments with similar economic characteristics. MFS generally focuses the funds investments in inflation-adjusted debt instruments issued by U.S. and foreign governments. MFS may also invest the funds assets in inflation-adjusted debt instruments of other issuers, other instruments with similar economic characteristics to these instruments, including derivatives, and non-inflation-adjusted debt instruments. MFS primarily invests the funds assets in investment grade quality debt instruments, but may also invest the funds assets in below investment grade quality debt instruments. MFS invests the funds assets in U.S. and foreign securities. MFS normally invests the fund's assets across different countries and regions, but MFS may invest a significant percentage of the fund's assets in issuers in a single country or region. The fund is a non-diversified fund. This means that MFS may invest a significant percentage of the funds assets in a single issuer or a small number of issuers. While MFS may use derivatives for any investment purpose, to the extent MFS uses derivatives, MFS expects to use derivatives primarily to increase or decrease exposure to a particular market, segment of the market, or security, to increase or decrease interest rate or currency exposure, or as alternatives to direct investments. Derivatives include futures, forward contracts, options, and swaps. MFS allocates the funds assets across countries, maturities, and types of debt instruments based on its evaluation of U.S. and foreign macroeconomic factors, including interest rates, inflation rates, and monetary and fiscal policies. MFS uses an active bottom-up investment approach to buying and selling investments for the fund. Investments are selected primarily based on fundamental analysis of individual instruments and their issuers. Quantitative screening tools that systematically evaluate instruments may also be considered. In structuring the fund, MFS also considers top-down factors. For purposes of the fund's 80% policy, net assets include the amount of any borrowings for investment purposes. Show less