i am trying to create a ticker for weekly market report for the company. my
problem is i am trying to create a sheet that do not need modification and
only to be updated.

i review 10 quotations for each product and want to create a function to
return the price differentials between the last Friday and the previous
Friday. also sometimes Friday happens to be a holiday so no quotations will
be posted on that day, therefore can this function take the previous day if
no price available on either fridays.

Example
Product X 100 $ (price diff)
(Price diff) is what i need to obtain from the sheet

first i started with the function TEXT(C26, "dddd") in seperate column then
used IF function with Vlookup, MAX, and MIN functions but it does not seem to
be working.