I need to find the result of

`((C1 * 5) + (C2 * 4) + (C3 * 3) + (C4 * 2) + (C5 * 1))/(5*6/2)`

.

I need to do it for 200 columns, not only 5. I currently use two sheets with sheet 2 containing a column of 200 down to 1.

The formula is `=SUMPRODUCT(C1:C200;$Sheet2.$C$1:$Shee2.$C$200)/((200*201)/2)`

. Sheet 1 keeps moving down to accept new data. Sheet 2 remains fixed.

Can this be done without resorting to a sheet 2?