Cash flow after taxes vs taxable income

[David Park]

Hello all, I'm new here. 

I'm reading Real Estate By The Numbers and I had a question: I was reading about Taxable income, which is the amount a property will be taxed in a given year by using the formula [Taxable income = NOI - Mortgage interest - Depreciation - Amortization]. Then I read later on about Cash flow after taxes that used a tax rate of 35% and used the formula [Cash flow before taxes = NOI - debt service - capital expenses + loan additions]. Why would someone use the Cash flow after taxes equation if I'm always going to use the taxable income formula to figure out how much I'm going to be taxed on?

Any help is appreciated, thanks.