Sum entire column in excel except for certain rows [closed]

Answer 1

You could use

=SUM(A:A)-SUM(A1:A2)

or, if you know that the cells you exclude are numeric,

=SUM(A:A)-A1-A2

Answer 2

=Sum($A$3:$A$1048576)

Should work

Answer 3

MrExcel has a couple of suggestions:

=SUM(A3:A65536)

OR

=SUM(A3:INDEX(A:A,MATCH(9.99999999999999E+307,A:A)))