Fourth and finally, as investors' demands for long-duration securities may have increased over the past few years, the supply of such securities seems not to have kept pace. The average maturity of outstanding Treasury debt, for example, has dropped by 1‑1/2 years since its peak in 2001, a trend just now beginning to turn with the Treasury's reissuance of the thirty-year bond. Corporations and households, however, have taken advantage of low long-term rates to lengthen the duration of their debt in recent years, which has compensated to some extent for the reduced duration of available Treasury debt.