it was during the twenties that special-interest provisions began to appear, stimulated into being by the complex of political forces that has accounted for their increase at intervals ever since. The first important one, adopted in 1922, established the principle of favored treatment for capital gains; this meant that money acquired through a rise in the value of investments was, for the first time, taxed at a lower rate than money earned in wages or for services—as, of course, it still is today.
