Total federal revenues doubled from just over $517 billion in 1980 to more than $1 trillion in 1990. In constant inflation-adjusted dollars, this was a 28 percent increase in revenue.3As a percentage of the gross domestic product (GDP), federal revenues declined only slightly from 18.9 percent in 1980 to 18 percent in 1990.4Revenues from individual income taxes climbed from just over $244 billion in 1980 to nearly $467 billion in 1990.5 In inflation-adjusted dollars, this amounts to a 25 percent increase.