Comment by pfdietz

Rough is doing heavy lifting there, so much so that I suggest it doesn't have any meaning except to say the population was growing. The growth from 1980 to 1960 certainly was not exponential: the percentage growth per year was all over the place, varying on the same time scale as the doubling time (or even faster).

https://ourworldindata.org/cdn-cgi/imagedelivery/qLq-8BTgXU8...

I suspect it's not a coincidence that the population bomb scare occurred right after the collapse of European colonialism, although teasing out the causation could be interesting.