Well, we all learned in school how to calculate an average: You take all the values you're averaging, add them up, and divide them by the number of values. This is fine if what you're trying to average is pretty uniform -- the average of 1, 2, 3, 4, and 5 is 3, right there in the middle. The problem is that averages are absolutely useless if a minority of numbers are unusually high -- the average of 1, 2, 3, 4, and 40 is 10, which doesn't help anybody know shit about anything.
"Unfair? That averages out to be 12 each!"
And that's the problem with the "average income" statistic -- a few rich people are skewing the shit out of the number. If you're earning less than the average income, it's not because your job is screwing you, it's because you live in the same country as Bill Gates, Mark Zuckerberg, and whoever owns Coke. Mr. Coke or whoever.
Why Does It Matter?
This is so stupidly obvious when explained, but it creates more myths by the day. For instance, you can see one study showing that for every 100 Americans, there are 88 guns, which could lead someone to reasonably assume that it's hard to find an American who isn't packing heat. Then you see another study from the same year showing that only 43 percent of households have guns in them. It's the same deal -- the people who have tons of guns skew the average upward ... and in the process make it hard as hell to get an idea of the overall picture. More often than not, telling us the average just muddles the issue.
"Every time you enter the room, I feel enormous. Thank you, mathematical averages!"
That's why most reputable sources who try to figure out wealth distribution use the median income, not the average. The median is the actual middle point: You get there by crossing out values on either end until you get to the center, which gives you a more relatable sum of around $50,000. There, we've just made 17 percent of you feel a little better about yourselves.