LINEST - exclude x variables and empty rows

Hi, all

I'm trying to populate a regression model here for multiple parameters here hence, I believe VBA can make my life easier.

1. Is it possible if the VBA to exclude the x variable(s) for LINEST() formula in cell range J3:M3 if the column(s) is/are empty?
2. Is it possible if the VBA to eliminate empty rows or rows with "BAD" data?
3. Is it possible if the VBA can populate the formula to each cell in column G (model) which has good data in instead of having the formula in every cell of the column?

Hereby I attached my Excel file. Hope anyone can enlighten me. Thank you so much!