Moving Average
I have a data set of >300 rows. I want to create a column that has the moving average of the previous 20 rows of the Results column. I want my new moving average column will look like thisrows 1 to 20 will be blank, row 21 will have the average result of rows 1-20 of the Results column, row 22 will have average results of rows 2-21 of the Results column, row 23 will have average results of rows 2...