Covariance matrix in Google Sheets for stocks

Question

I'm trying to use a template to see what it says about my stock portfolio. it uses a covariance matrix with the data from excess returns. The template instructions say to use an add-on to calculate the matrix but the add-on doesn't work. I tried a formula but it didn't work. =MMULT(TRANSPOSE('Excess Returns'!B3:F252),'Excess Returns'!B3:F252)/251

I've got 5 stocks and 249 dates of data. in a video I watched on how to make a matrix it says to highlight the 5x5 matrix and hit control shift enter and it will apply the formula to the grid but it doesn't work.

Do you anyone no what i am doing wrong or a better way of doing it?

Answer 1

this is the template https://docs.google.com/spreadsheets/d/1yS26o6VA12Ry7aZVzObQ7LhyD4uRznNcdOgVzpkSwFQ/edit?usp=sharing

and this is the reddit post with other info https://www.reddit.com/r/stocks/comments/crmpx7/i_made_a_portfolio_optimisation_tool_spreadsheet/

this is my post, but i guess i posted it as a guest and then made an account so idk.