Hi Sam, it works!! you are great..thank you very much!!

and finally, as I wrote at the very beginning, I need to get the result of the second equation into the column C

the second equation is similar to first one, I attach the excel file with my manual calculation and pdf file to see the equation in real (see third equation BV_t),
just notice please that the number 94 that I use in the last step of the manual calculation stays for number of rows that are used for the calculation in given csv file,
thus it will be different in every csv file (it is not a constant), I believe there is a code in VBA that generates that number

btw I am writting to Jacob about the contribution, thanks again

table_abbv_test.xlsx
http://ulozto.cz/x1LUbSuS/bv-calculation-pdf