And when those entries are laid end to end in a timeline, as Dr. Walsh has done in a paper published last week in Environmental Science and Technology, they shatter a lot of myths.

The much-lauded greatest generation of the 1920's and 1930's, for example, threw out far more garbage, Dr. Walsh found, than New Yorkers living today in the era of shrink wrap and single-serve. Pounds of trash per person peaked not in the prosperous 1990's, but in 1940.