Iran did not actually increase the number of winners. Napal increased fro, 4370 winners to 6082, that is 39% increase. The rest of Asia increased from 5646 = 16045 - 6029 - 4370 to 11161 = 23270 - 6027 - 6082. That is 1.98 times increase. If 11161 others is achieved at 27000 (as we saw), then 16045 (necessary to provide all visas for quota) will be achieved at number 13658 = 27000/11161*5646
Basically, we assume Iran will have a limit and Nepal will have a different limit.
How to check that?
Take all Nepalese numbers you know and see if they are all under a limit below 27000. Do the same for Iran.
Limit for Iran could be at the level of about number 11000, and limit for Nepal at the limit of about number 13700.
Then passing level would be about the same 13700.