In one of the Mocks or practice questions on CFA site, I believe the Grinold-Kroner formula was used incorrectly. Please correct me if I’m wrong.
In the problem, P/E changed from 15.6 to 15.0 and the example stated that the difference in P/E that was used in the formula was -0.6% (15-15.6)
I believe this is incorrect. The change in P/E should be (15 / 15.6) - 1 = -3.85%
Could someone please verify if I’m right or wrong?