When I took astronomy in college around 1960, we were told about the 11 year sun spot cycle, and also an 88 year mega-cycle. Subtracting 88 from 2018 give us around 1930, a period of intense drought, dust storms and the Great Depression. The 11 and 88 figures are not absolute, but an approximation. Peaks and troughs also last for several years. Could be 10, 14, 86, 90, etc. See charts in link below. The charts can be clicked to magnify them.
https://en.wikipedia.org/wiki/Solar_cycle
Thanks glee’. Use of the term cycle for natural phenomena always appears to be scurrying humans’ attempts to find order in the overall chaos of reality. I do enjoy reading about mathematical relationships between, say, planetary motions and solar activity — but alas, there’s no widely accepted model for causational relationships. Here are some optimists:
Jackpot! Jupiter and Saturn – Solar cycle link confirmed
https://tallbloke.wordpress.com/2011/08/05/jackpot-jupiter-and-saturn-solar-cycle-link-confirmed/
Jupiter’s Dance
https://www.jupitersdance.com/