I have a numerous sets of data that varies from set to set in the amount of
rows each contains (one set will contain 2135 rows and one will have 3784
rows, etc.). Each set has 12 columns. I have some formulas set up that do
various calcutions on the data.

As things are now I am having to copy and drag the formula's down to match
the end of the data. I also have to enter a formula that calucates the sum
of one of the columns. This is very time-consuming.

Is there a function/formula/option that will fill in my formula all the way
to the end of the rows of data, no further? Is there a
function/formula/option that will then calculate a the sum of a column of
"x"-amount of rows?

Assume the sum of column E.