» Avoiding Errors when Using the And Function to Combine Multiple Conditions in Array Formulas
CATEGORY - Excel Date & Time Formulas
VERSION - All Microsoft Excel Versions
The following Array formula was designed to calculate the average difference between each pair of values in columns A & B (providing both cells are not empty):
{=AVERAGE(IF(AND(ISNUMBER(A1:B5),ISNUMBER(A1:B5)),A1:A5-B1:B5))}
However, an incorrect result of "0" is returned.
Solution:
Use the AVERAGE, IF, and ISNUMBER functions as shown in the following Array formula:
{=AVERAGE(IF(ISNUMBER(A1:A5)*ISNUMBER(B1:B5),A1:A5-B1:B5))}
Book Store:
Recommended Books:
- A Mathematician Plays the Stock Market
- Microsoft Excel Version 2002 Step by Step
- Infectious Greed: How Deceit and Risk Corrupted the Financial Markets
- Cashflow Quadrant: Rich Dad's Guide to Financial Freedom
- The Basics of Finance: Financial Tools for Non Financial Managers
- Microsoft Excel 2002 Visual Basic for Applications Step by Step
Should have more documentation
John
I mean, why does this work? A little more explanation is needed.

