Around 20,000 to 25,000 must have applied this year, but about less than half would have actually appeared, as has happened in the last 2-3 years.

The trend over the last 4 years is as follows:

Year---Candidates appeared
2012: 10066
2013: 11406
2014: 13170
2015: 12176

There was a huge surge in CSS popularity near 2010, however it seems to have peaked (currently) in 2013 with 13,170 candidates actually appearing.

My guess would be that this year about 11,000-12,000 candidates would have appeared.

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