Mean vs median in income and age

It's a pretty open-ended question, and there are whole classes on the subject, but in short, there are two answers. "Average" is usually synonymous with mean. However, particularly with income, median tends to be used more often, as the mean is affected by outliers. The median income-earner, who's earning more than half the population and less than the other half, is earning much less than what is "average", as income is concentrated among the highest earners (I'm starting to sound like a different Bernie here, but this is just math). If you have a population of 100 and the 3 highest income earners quadruple their income over a decade, but the 97 lowest income earners don't increase their income at all, the average will go up, but the median will be unchanged, closer reflecting reality for most people.

This blog post might do a better job explaining (I just found it by googling mean vs median): fredblog.stlouisfed.org/.../

Well said Bernie. All I would add is that sometimes it makes sense to use income per capita, a sort of average, if you want to know how much money is floating around compared to population. it an be a shorthand for how much financial support a government can expect compared to people who could need services. Very high in municipalities of empty-nest celebrity mansions -- one year Fisher Island FL off Miami was the highest in the nation, very low in modest neighborhoods with lots of children. .  

Well said Bernie. All I would add is that sometimes it makes sense to use income per capita, a sort of average, if you want to know how much money is floating around compared to population. it an be a shorthand for how much financial support a government can expect compared to people who could need services. Very high in municipalities of empty-nest celebrity mansions -- one year Fisher Island FL off Miami was the highest in the nation, very low in modest neighborhoods with lots of children. .