Currently, repayments of principal from agency debt and MBS are not being reinvested, allowing the holdings of those securities to run off as the repayments are received. By contrast, the proceeds from maturing Treasury securities are being reinvested in new issues of Treasury securities with similar maturities.
At some point, the Committee may want to shift its reinvestment of the proceeds from maturing Treasury securities to shorter-term issues, so as to gradually reduce the average maturity of our Treasury holdings toward pre-crisis levels, while leaving the aggregate value of those holdings unchanged. At this juncture, however, no decision to change reinvestment policy has been made.