In general, the dollar is well down from the early 1980s, but up from its early 1990s lows. These percentages are affected by changes in exchange rates; no doubt the late 1980s decline was partly the result of the post-Plaza decline in the US$'s value. But as the $ has risen since 1995, there hasn't been any corresponding increase in reserve market share.
US$, % of total FX reserves (1998 and 1989 IMF annual reports)
1998 AR 1989 AR 1980 68.6% 1981 71.5% 1982 70.5% 1983 71.2% 1984 69.4% 1985 64.2% 1986 66.0% 1987 66.8% 1988 54.6% 63.3% 1989 51.4% 1990 49.4% 1991 50.0% 1992 54.2% 1993 55.6% 1994 55.7% 1995 56.4% 1996 59.6% 1997 57.1%
Doug