I have 3 ranges

1. week number
2. Rep code
3. Product value

how do i count the number of weeks that pertain to a specific rep code i.e
countif rep code is equal to 101 and week number is wk 1

Also how do i sum the product value if the weeks relate to say week 1 and
rep code is equal to 101

1 £450 104
1 £1,000 106
1 £1,000 102
1 £800 106
1 £500 106
2 £2,000 102
2 £2,200 104
2 £1,230 104
2 £1,000 102
2 £1,000 108

I want to link the details in to a weekly tracker for sales reps but the
values might change so I can't use filters

Thanks

Garf