According to later posts on this, many calculations which involve storing 65535 or 100000 really store the other one:

Dana DeLouis writes: """

And if you multiply be say, 2 you get something else:

=A1 MUL 2 returns 131070, as if A1 had 65535. (which it should have been)

=A1 MUL 1 Keeps it at 100000.

=A1-1 returns 65534

=A1/1 is still 100000

=A1/2 retuns 32767.5 """

Given that it would more often be the case that 65535 or 100000 comes up as an intermediate number than the final result, it could be that there are many calculations that have been done in error silently for those using Excel 2007.

EDIT: Replaced asterisks with MUL because I don't know how to escape them.