Maybe of the decade. New Census figures show that the typical American household made less money last year ($50,303) than in 1998 ($51,295). In the four decades that the Census Bureau has been tracking this stuff, this is the first time that median income actually fell (all numbers adjusted for inflation). From NYT's Dave Leonhardt:

What's going on here? It's a combination of two trends. One, economic growth in the current decade has been slower than in any decade since before World War II. Two, inequality has risen sharply, so much of the bounty from our growth has gone to a relatively small slice of the population.