If we use 19, then 2/(n + 1) = 2/20 = 1/10 = 10% weight for the most recent data point.


My guess is that 2 is just the smallest number you can put in the numerator. If you used 1/(n + o), maybe the weight of the current number would not be "exponential."


But you don't want to use the same formula as everyone else anyway, unless by design.


eLROY