On Nov 19, 5:22*am, Mike wrote:
The "" will leave the cell empty
=IF(A1<100,A1,"")

I beg to differ. By definition, the cell is not "empty"; it has a
value or formula. Test with ISBLANK(). (Sadly, a misnomer.)

Instead, that formula will cause the cell to be __displayed__ as if it
is empty (if A1 is not less than 100). But the fact is: the cell
will result in a text value, namely the null string. This has
consequences different from a truly empty cell.

For example, if that formula is in A2, the formula =A2*something
results in a #VALUE error (if A1 is not less than 100). In contrast,
if A2 were truly empty (no value or formula), =A2*something results in
zero. IMHO, Excel is inconsistent about how cells with null strings
are handled. Some functions treat those cells as zero; others return
a #VALUE error. Use the N() function around references to cells in
which you mix numeric and null-string values.

Be that as it may, the OP explicitly ruled out this solution.