Are open tech report sites taking off in CS ?

For a while now, the math and physics have amused themselves by wondering why the CS community is slow to adopt the arxiv. In the past year or so, I've noticed an uptick in postings on the arxiv (especially around conference deadlines).

Prompted by David Eppstein's review of 2010 in cs.DS, I decided to get some stats on publication counts at the arxiv and ECCC for the past four years. My method:

1. go to arxiv.org/list/FIELD/YY (thanks, David)
2. Read off the total number of papers listed

For the ECCC, papers are numbered by YEAR-COUNT, so looking at the last paper published each year sufficed to get the count.

I did this for cs.{CC, DS, CG, LG} (LG is machine learning/learning theory)

Caveat: I ignored cross submissions, so there's some overcounting. I'm hoping that at least to determine trends this is not a major issue.

Here are the results:

Overall, it's clear that arxiv submissions in theory CS are climbing (and rapidly in the case of cs.DS), which I'm quite pleased to see. The growth rates themselves seem quite steady, so it's not clear to me whether the fraction of papers going on the arxiv is itself increasing (there's good evidence that the total number of papers people are writing in general is increasing).