Rounding To the Nearest Even Integer

Chuck asked if there was a way in Excel to force rounding to the nearest even integer. He expressed this desire based on some statistical analysis that he was doing.

There are several ways that you can round to the nearest even integer, but the answer you select depends on how you define "nearest." For instance, if the number you want to round is 13, is the nearest even integer 12 or 14? Does the answer change if dealing with negative numbers, as in -13?

If you believe that the next even integer is always away from zero, then you can use the EVEN function, which always rounds to the next even integer away from zero. Thus, -13 is rounded to -14, and 13 is rounded to 14. This may work great when rounding integers, but it doesn't work that great if you are rounding non-whole values. For instance, EVEN rounds 12 to 12, but rounds 12.1 to 14, even though 12.1 is clearly closer to 12 than to 14.

If the numbers you are rounding are non-whole numbers, you'll need a formula. The following formula will work for this purpose:

=INT(A2/2+0.5)*2

Assuming your non-rounded value is in cell A2, this formula divides the value by 2 and then rounds that value to an integer, and then multiplies the result by 2. What this means is that all values, 11.1 through 13, are rounded to 12. (This works for negative values, as well.)