Since various strategists continue believing that the foals breeding level change has had the opposite effect than what it was meant for, here are some numbers:
01 Aug 05:02 - 31 Aug 05:02 : 5620 foals, Unwanted foals: 4404 (79%)
01 Jul 05:02 - 31 Jul 05:02 : 4751 foals, Unwanted foals: 3279 (70%)
01 Jun 05:02 - 30 Jun 05:02 : 10690 foals, Unwanted foals: 8714 (82%)
01 May 05:02 - 31 May 05:02 : 18187 foals, Unwanted foals: 14295 (79%)
01 Apr 05:02 - 30 Apr 05:02 : 19489 foals, Unwanted foals: 14722 (76%)

'Unwanted foal' was considered a foal that has not advanced past level 9.
As you can see, the % of the 'unwanted foals' is roughly the same, but the numbers are 3-4 times lower.
The breeding change took place on May 27th.