by Jacob Goldstein

The very rich take home a much bigger chunk of the nation's income than they did a few decades ago. Slate's Timothy Noah is rolling out a big project trying to figure out why.

Here, in two graphics, is what the shift looks like:

Top Earners
Catherine Mulbrandon/via Slate

Top Earners 2
Catherine Mulbrandon/via Slate

So far, Noah has looked at gender (not a factor) and immigration (a factor). He'll be looking at other issues — technology, trade, government policies, organized labor, education, etc. — over the next few weeks.

For more: See our tax-day post on taxes and the very rich.

Planet Money Question of the Day: Why did the rich get so much richer? Post your answer in the comments section.