48-year cycle

I remember when I was a kid reading "The Great Depression of 1990", which mentioned the Kondraetiff cycle, which was 51 years long.  But what if the modern version of it is about 48 years long.

Compare October 28-29, 1929 (when the stock market dropped 24% over the two days) with October 19, 1987 (when the stock marked dropped 23%).  Of course there were major differences, since the 1987 crash did not cause a recession, but this shows the 48-year cycle.

I've already mentioned Trump and Nixon, but look who was president 48 years before Nixon - Warren G Harding, whose administration was scandal-ridden.