SUMIF is faster, particularly with larger arrays.

The -- converts the True/False values to 1's and 0's to be used in the
SUMPRODUCT formula, and yes, it can be used in other formulae to
convert Boolean values to numeric.

Hope this helps.

Pete

On Sep 12, 9:16 am, yshridhar <yshrid...@discussions.microsoft.com>
wrote:

Hi

I would expect the SUMIF to be faster.

The use of the double unary minus -- is to coerce the result of the test
SCHOOL!$J$1:$J$950=$B$1
from True False to 1 and 0, so they can be multiplied by the values in
V1:V950.
The results of that, either the value from column V where J = B1, or 0 where
the value in J does not equal B1, are then summed to produce your result.

For more help on this topic read the excellent documents by
Bob Phillips at
http://www.xldynamic.com/source/xld.SUMPRODUCT.html

or by JE McGimpsey at
http://www.mcgimpsey.com/excel/formulae/doubleneg.html

SUMIF is much quicker, SUMPRODUCT whilst not being an array function acts
like one, and suffers the overheads of that.

See http://www.xldynamic.com/source/xld.SUMPRODUCT.html for a detailed
explanation. If you remove it it won't work as explained. And yes it can be
used anywhere, such as

Try

=10>7

and

=--(10>7)

and see the difference.