Where you start matters. When comparing numbers over time, you can slant the comparison by choosing your starting point. Say the Chicago Cubs lose 5 games, then win 4, then lose 1. You can truthfully say that the Cubs have lost 6 of their last 10 games (sounds bad) or that they have won 4 of their last 5

(sounds good).

The median income of American families (in dollars of 2004 buying power)

was $50,705 in 1996, $54,285 in 2002, and $54,061 in 2004. By what percentage did family income increase between 1996 and 2004? Between 2002 and 2004?

You see that you can make the income trend sound bad or good by choosing your starting point.