Look at the yield-curve animation found at the SmartMoney Website,
https://www.smartmoney.com/onebond/index.cfm?story=yieldcurve.
Make a note of the overall level of the yield curve from about mid-1979 to mid-1982. Compare that with the level of the curve for most of the 1990s. What accounts for the differences in yield-curve levels in these two periods?