I think you are wrong about this. Here is what the Prentice Hall Documents Library says, in part, about the Tax Reform Act of 1986:
Other features of the Tax Reform Act of 1986:
Tax cut. The top marginal tax rate on wealthiest individuals was reduced 44% (from 50% percent to 28%). The marginal rates for leass wealthy individuals were also reduced, but not by as high a percentage. Tax reductions were said by some critics to underly the massive mushrooming of the federal deficit during the Reagan administration.
Here is the link.
Also, the more you keep posting on this, the more I keep recalling the other "hikes" involved. Note the end of the investment tax credits, which DRAMATICALLY increased the real tax in investments.