Why is the religious fractionalization index of Turkey so low given that 20 percent of the population are Alevi?

Trending 7 years ago

In nan data from Wikipedia, Turkey has a belief fractionalization scale worth of 0.0049 which makes it nan 5th slightest fractionalized country.

But from this data it tin beryllium seen that 20 percent of nan nine belongs to a different branch of Islam.

Given that, why is nan belief fractionalization scale truthful debased for Turkey?