For no particular reason, we were inspired this week to go back and look at the Census Bureau's historic data on voting trends by race and age. Perhaps it was all of the talk of 2016. Perhaps it was knowing that there were tables of numbers sitting out there, waiting to be charted. Who knows what motives lurk in the hearts of men?

Anyway, doing so reminded us of a few things: First, that younger people are much more erratic in their voting during presidential years. And, second, that younger people now vote less frequently than young people did 50 years ago -- and that older people vote more frequently. (The graphs below use turnout as a percentage of total voting-age population rather than the citizen voting-age population, meaning that the percentages are lower than you might expect.)

We've explored this a few times in the past. We've noted that 18- and 19-year olds go to the polls more regularly than slightly older voters (at least in California), perhaps due to the novelty of the thing.

Looking at (citizen) turnout by age and race -- as on the giant graphs below -- suggests that two patterns overlap: Younger people vote less frequently, and white people usually vote more heavily than black people, who in turn vote more heavily than Hispanics.

But notice here the groups of black and white older voters in 2012. The group with the highest turnout that year, according to Census estimates, was black people over the age of 65. The youngest group of black voters saw a spike in 2008, but by 2012 had returned to previous turnout rates. Turnout among the youngest group of white voters in 2012 dropped dramatically.

The lowest turnout groups are consistently the youngest. The results from 2012 suggest, though, that turnout layering is far from set in stone. Which at least one 2016 candidate (name rhymes with "banned haul") already seems to be counting on.