Every Monday, Freddy, "the numbers guy" of ACME Widgets Incorporated, downloads a spreadsheet of the widget production data from the past week. He opens it in Excel and writes some formulae to summarize the data, which he then presents ACME Widgets' CEO.

Every week Freddy is putting the same formulas into the same spreadsheets. Each week's spreadsheet has the same columns but a variable number of rows, as the number of data points fluctuates.

What is the most efficient way for Freddy to summarize the spreadsheet data each week? Copy-and-paste the formulae?

(Freddy really likes Excel. He doesn't want to learn Matlab, R, Julia, Python, Fortran, jQuery, or how to delegate.)