I’m trying to get a rough estimate of the number of people alive today in the US who were at least 14 years old in the years 1975-1980, but I’m having a hard time figuring out how to do it.
So I need:
–US population 14 & over in 1975
–Plus everyone who turned 14 in each year of 1976-1980
–minus everyone from that total who’ve died.
If I’m reading your question properly, you don’t need all that information to get your answer.
On July 1, 2015, everyone alive that’s 49 or older and roughly 1/2 of the 48-year-olds would have been 14+ at some point in 1975-1980. Open this file in your favorite spreadsheet program; it’s got the most recent population estimates for the US (as of the aforementioned 7/1/15, column J) broken down by age (column A) and sex (column B: 0=all, 1=M, 2=F).
Half the 48-year-olds + everyone older = 117,164,384 people.