Why CFA Level 1 December Pass Rates are LOWER than June Pass Rates

[DDPH]

Except for one year (2004), December pass rates are never higher than same year June pass rates. Maybe coincidence or lack of statistical evidence for the following theory but here’s what I think:
-CFA Institute is NOT making the test harder in December. That just wouldn’t make sense.
-It is safe to say that the December test taking pool has a large component of re-takers that didn’t pass in June. So, this pool is inherently made of slightly less skilled test-takers (don’t want to call them something else) than the June pool is. Therefore, even though the test is still curved (it is only the top 1% that set the curve so the curve is probably the same as in June), the passing rate is probably lower in aggregate than in June because of this reason.
Thoughts?

 

[blackomen]

DDPH wrote:
Except for one year (2004), December pass rates are never higher than same year June pass rates. Maybe coincidence or lack of statistical evidence for the following theory but here’s what I think:
-CFA Institute is NOT making the test harder in December. That just wouldn’t make sense.
-It is safe to say that the December test taking pool has a large component of re-takers that didn’t pass in June. So, this pool is inherently made of slightly less skilled test-takers (don’t want to call them something else) than the June pool is. Therefore, even though the test is still curved (it is only the top 1% that set the curve so the curve is probably the same as in June), the passing rate is probably lower in aggregate than in June because of this reason.
Thoughts?

I’d think by your reasoning the Dec pass rate will be higher if there are more retakers who have already seen the exam and prepared for it before.

 

[misswallstreet]

I think it’s because the new curriculum is partially tested on the June takers. So by Dec there are less questions to throw out and hence less of a curve.