I was confusing Margin and MarginCost.

I am using data from 2010 to 2022. However, I found out that the PIP size was 0.0001 up until Jan 9th, 2016, and it was reduced to 0.00005 onwards. Is it reasonable to inspect the date per ar, and change PIP after that date? what is the best way to deal with changing the PIP size in historical data so that the performance metrics are accurate?

Thanks