Naive Generational Influence

"Good Warriors"? Who chooses these names?

Reading yet another article trying to assign generational responsibility for the current state of America I realized that I didn't have the best grasp of generation definitions or population distribution across the decades. That inspired me to whip up a quick spreadsheet to compute a simple measure of political influence across time, under the premise that ultimately responsibility lies with the electorate. Since generation definitions are debatable and birth rates can vary a lot I did it year by year and then turned it into a generational overview afterward. The goal isn't to directly make any responsibility assignment (an arguably pointless aim) but to examine what people's contribution over time would've been minus any idiosyncratic events (i.e. all other factors being equal) and therefore provide a better starting intuition for such factors.

Births in a given year: I neglected the issues of infant mortality, woman's suffrage, slavery, and voter suppression generally as this is intended as a rough analysis only and those can arguably be included in the historical idiosyncrasies I mentioned earlier. Here is the birth data by year, which required going back as far possible so that boundary issues are minimized.

Years of political activity: As an estimate of the years during which an individual can have political influence on society, I chose a starting age of 18 and an ending one of 75. All years are counted, not merely election years as political activity can (and should) extend beyond the mere act of casting a ballot. This chart shows the number of voters in each generation of interest that are in the age range of 18 to 75 over time, with preceding generations lumped together.

Political Inertia: To reflect the time it takes for the course of events to be altered, I employed an exponential decay model. Here is the generational influence with a couple choices of decay rate:

Since exactly what decay rate to use is difficult to determine, I plotted the share of generational responsibility for the state of affairs at the end of 2017 across the entire range of possible values:

The values approach a limit fairly quickly and quite a bit of the full range is rather extreme anyway, so here is the area with a decay rate less than ten percent:

Even given the simplistic nature of this analysis, it's pretty clear that one group shares little responsibility for the current state of affairs (for good or ill): New Boomers, or "Millennials" to use the more common label. Additionally, for all their numbers, Baby Boomers maximum value of impact for any choice of decay rate is 32.5%. While certainly not a small share, previous generations had a vast, ongoing influence.

More generally, I would argue that this basic model serves as a useful basis for considering more nuanced historical, societal, and psychological influences. I also would strongly advise against assigning more significance to it beyond that. Indeed, the major takeaway is that previous generations didn't simply evaporate once newer ones came of age. Patently obvious, but not properly reflected in the tone of many articles on the topic I come across.