#NUM error message when attempting to do sum

[TallulahBea]

I am new to Excel, and have never had any training. We use a database for work that was set up by someone with a high level of IT skill. Since he left, we have been inputting the data. I now need to produce a report using the database and am experiencing an error when attempting to calculate averages, or medians.

There are several columns I need to produce this data for. It is a patient database, so some of the averages are for waiting times for all patients, and some are average % changes for a walking test and for subjective tests on patients' mood. The changes for each pt are automatically calculated via a formula, which was set up for us.

When I attempt to do sums to find averages for all the patients, I get a #NUM message. As I said, neither I or my colleagues are very IT or Excel savvy, so are now pulling our hair out with a huge database from which we cannot get the data we require.

Any help, explained in simple terms please(!) would be much appreciated.

[:) Sixthsense :)]

Below are the possible causes of #NUM Error

• The wrong data type might be supplied in a function that requires a numeric argument.
• The formula might use a worksheet function that iterates (iteration: Repeated calculation of a worksheet until a specific numeric condition is met.), such as IRR or RATE, and that function cannot find a result.
• The result of a formula might produce a number that is too large or too small to be represented in Excel.

To get rid of #NUM Error

Make use of IFERROR FUNCTION.

IFERROR(FormulaORvalue, value_if_error)