TITLE: Amount of math research published in other languages?
QUESTION [27 upvotes]: I'm curious what languages contribute the largest fraction of published research mathematics. That is, for a given language the percent of new research being published in that language. I'm especially curious to see how you come up with such numbers.
From some googling I managed to get a very crude estimate of total publication volume: 28643 arXiv articles in 2014. Looks like arXiv sometimes has articles in other languages but I can't search by language.
Edit: Thanks S. Carnahan for pointing out that I could search the full text by common words from different languages!

REPLY [14 votes]: I researched the language distribution using the Web of Science. Since your interest was in new content, I restricted the search to the period 1985-2015. The total number of mathematics articles in that database is 882565 for this period. Here is the breakdown by language:

[1985-2015]

The Web of Science goes back to 1945, so I also made the search for the entire period 1945-2015. That gives a total of 1120170 mathematics articles, with this breakdown by language:

[1945-2015]

Finally, for the last ten-year period 2005-2015 the breakdown (for a total of 459213 mathematics articles) is 

[2005-2015]

It is clear that the coverage of Web of Science is not representative for Asia, but for the European languages I would expect it to give a reliable breakdown.