What did the 1920s and 1930s have in common?

Question

What did the 1920s (roaring twenties) and the 1930s (dirty thirties) have in common?

Only one I can think of is that radio was still popular among everyone..

Answer 1

This link provides historical similarities of Roaring 20's and 1930's
http://www.snowcrest.net/jmike/20sdep.html

The Washington Times reports there was a global warming scare in the 1920’s and 1930’s.
http://www.uncommondescent.com/global-warming/global-warming-roaring-20s-style/
This was one of several such articles I have found at the Library of Congress for the 1920s and 1930s," says Mr. Lockwood.
http://www.washingtontimes.com/article/20070814/NATION02/108140063

Answer 2

Great Depression?

1928-1939