The fund is passively managed to provide exposure to the short-term pocket of the US treasury debt market, excluding inflation-protected bonds. It includes short-term US treasury securities including bullet, putable, sinkable/amortizing and callable bonds, as well as original issue zero coupons. The fund excludes securities that are separate trading of registered interest and principal securities (STRIPS), as well as certain special issues, such as state and local government series bonds (SLGs) and inflation-protected securities. The fund uses a sampling technique to track its index, in which it holds a range of securities that has the same return and risk characteristics of the underlying index.