In an earlier post, I used Google Books Ngram tool to show that the frequency with which popular Chinese foods were mentioned in printed books corresponded closely with the opposite trends in popularity of chop suey and dim sum over the past half century or so.  
As a followup, I checked on how well these iconic Chinese foods compared with 'fortune cookie' and 'fried rice,' two other very popular Chinese restaurant foods.  The results below show that by the early 1980s dim sum was mentioned more often than the ubiquitous fortune cookie, but by 2008, the gap was narrow.  Surprising, to me, was that fried rice easily outdistanced all of them, rising in a linear rate over the past century.  Wonder if 'Southern Fried Rice' was a contributing factor. (-: 

 
 

   Of course, an easier method to determine food preferences might have been to poll a few Chinese restaurateurs!  But it is nice to see that dissimilar methods yield convergent conclusions.  Ngram is a neat tool, and can be used for many other analyses having nothing to do with food.  Note also, as shown at the bottom of illustration, if you click on the link for a given food and given time period, google will take you to its findings of the actual occurrences of that item in books. (Note: You can't do that with the image above, but need to do that from your browser)