Is it a table, a lookup, ? range always changing

[scott2020]

I download a .csv daily In the columns the following headers, Meter, serial num, value, uom, day, wk#, timestamp, and a few more rows of usless info.
the meter name changes, the serial num, and the value changes. I added the columns for day, and week# in to make it easier I though. I use the timestamp and regular formulas to fill in the data based on the timestamp.
This give day of week and week number i.e. 1 to 52 for the year. Then I parse all the data to their own tabs based on the name. All in vba.
What I can't wrap my head around is I may have 25 rows with a week 1 value, and what I would like to do. is, based on the week number, take the value in the value column C, find the min/max of those rows. Subtract the difference, ignoring repeated values. This will have to happen with an output to a cell every week. So the wk# number of course is going to change. Any ideas?

 

[scott2020]

I download a .csv daily In the columns the following headers, Meter, serial num, value, uom, day, wk#, timestamp, and a few more rows of usless info.
the meter name changes, the serial num, and the value changes. I added the columns for day, and week# in to make it easier I though. I use the timestamp and regular formulas to fill in the data based on the timestamp.
This give day of week and week number i.e. 1 to 52 for the year. Then I parse all the data to their own tabs based on the name. All in vba.
What I can't wrap my head around is I may have 25 rows with a week 1 value, and what I would like to do. is, based on the week number, take the value in the value column C, find the min/max of those rows. Subtract the difference, ignoring repeated values. This will have to happen with an output to a cell every week. So the wk# number of course is going to change. Any ideas?
View attachment 7787

never mind, i fixed it myself. i was using max(if, and changed to maxifs, and added more to the criteria, the rest was easy