This was very helpful......
After putting the variables into watch mode, I think that I get a better sense of how/why this works the way it does.

I'm sorry I didn't better communicate that the main purpose of this was to utilize the Xrng/Yrng in a linest function.

The immediate goal I'm trying to achieve is to calculate the coefficients, T-stats, and R-squared for each of the combinations.

So I modified - slightly the code you provided to try to achieve the first part of this goal - get the regression and then spit out the coefficient/T-stat of first variable. Eventually, I have to do all variable coefficients/T-stats.

Now the problem I'm facing is that there is some kind of mismatch - on the linest with the xrng. I know this because when I put in a fixed range into the code - it works fine.

Thoughts?

Appreciations in advance!

Marston