Two Americas: Those who use the coersive power of the government to take money for themselves, and those who have to earn it by giving value for money in non-coerced , arms-length transactions.
Via Carpe Diem, which has more thoughts on the trend
Note: I have seen folks defend this type of chart by saying it is just the function of the inflection point of a normal distribution creeping by inflation across a dividing line. But look the $180K+ in 2010 vs. the $150K+ in 2005. By inflation, a $150,000 salary should not have increased to more than $165,000, but we see more than twice as many people making $180K plus today than made $150K plus five years ago.