This is the lowest number of submissions in several years, and the highest acceptance rate since 2001.
The other interesting thing is the apparent lack of papers by “real” economists. It makes one wonder how much interaction there is between the two sides of the Econ/CS “community” and whether this is just turning into an echo chamber.
It’s a bit hard to be too worried about the decline in number of submitted papers, as there are now several alternative venues directly aimed at AGT (e.g. SAGT and COMSOC which are pretty new), and with the high numbers of AGT papers submitted to general conferences (in TCS, AI, e.g. ICS which is new).
One may certainly question the PCs decision to increase the acceptance rate, but as far as I understand, this was a deliberate decision due to a certain widening in the scope of accepted papers.
The PC chairs wrote in an email to the PC that “It [the high acceptance rate, AP] is almost exclusively due to the large number of very high quality submissions we received this year.” My anecdotal impression as a PC member was that the quality of submissions was indeed very high, and it seems the acceptance threshold was naturally high as well.
Picky comment: COMSOC is non-archival so it should not have an impact on the number of submissions to EC.