TTax Effective Tax Rate

On the instruction page of my return , Turbo Tax shows an effective Tax rate.

I looked at everything and that number is the Tax/AGI.   Not sure why they call that the effective tax rate. Most definitions of effective tax rates are Tax/Taxable income.  

If you Google it or look at it in INVESTOPEDIA, effective tax rate is taxes/taxable income so this rate from TT is not effective tax rate. I dont know what tax/AGI is actually called.  Maybe that is total effective tax rate? *based on total income, not taxable.  Or we can say,... effective taxable tax rate and effective total tax rate? idk.