Pondering sustainability through an xkcd lens took me to other “green” ngrams. As described by xkcd, the graph represents the frequency of the use of each word in Google books, 1800-2008:
Then I checked what we eat:
Ngrams should provide some pretty good clues about our resource use.
Sources and Resources: If you want to investigate our ngram further, add some words or check out their math, do go to my ngram viewer. And here is some recent insight about ngrams from the Atlantic. For more xkcd, here is “sustainable.”