Which tax reform was implemented under President Reagan in 1986?

The tax reform implemented under President Reagan in 1986 was primarily characterized by a significant decrease in the top federal income tax rate. This reform aimed to stimulate economic growth by reducing tax burdens on individuals and businesses, effectively encouraging investment and consumer spending. The Tax Reform Act of 1986 not only lowered rates but also closed loopholes and broadened the tax base, which helped to create a more efficient tax system.

The decision to decrease the top tax rate was rooted in the economic challenges of the time, including high inflation and sluggish growth. By reducing taxes, the Reagan administration sought to promote a pro-growth environment. This action was part of a broader economic strategy known as "Reaganomics," which focused on supply-side economics.

In contrast to the other options, the 1986 tax reform did not involve increasing the top tax rate, eliminating federal income taxes, or implementing a flat tax system. Each of those alternatives reflects different economic philosophies and tax strategies that were not part of the 1986 Tax Reform Act.