First Time Yield=
#UnitsPassing1stInspection/#UnitsInspected
approx= e^-DPU
RolledUpYield=
#UnitsCompleteingProcess/#UnitsProcessed
approx= e^(DPU1+DPU2+DPU3...)
where DPU1, DPU2, DPU3 represent the defect rate of process steps 1`, 2, 3, ...
I am just getting started in six sigma and, I feel overwhelmed by all of the Mathematical formulas that are used to calculate the most common used functions of six sigma, I guess I need to get familiar with the most commonly used calcualtions.