So, I have a data set of percentages like so:
100 / 10000 = 1% (0.01)
2 / 5 = 40% (0.4)
4 / 3 = 133% (1.3)
1000 / 2000 = 50% (0.5)
I want to find the standard deviation of the percentages, but weighted for their data volume. ie, the first and last data points should dominate the calculation.
How do I do that? And is there a simple way to do it in Excel?