Hi All - I am trying to calculate and plot the St Dev on a metric as the sample size grows. The attached Excel sheet shows a sample data set with 20 tests and the associated speed result. After 2 tests, I can calculate the St Dev of those 2, add the 3rd test and St Dev changes, all the way to the last test.
I cannot for the life of me figure out how to do this in Tableau! Please help!