Jacek,

You can only select one value, not all. You could add a thirteenth value
"All Months", and then deal with that however you need to...

HTH,
Bernie
MS Excel MVP

"Jacek" wrote in message
...
Hi,
I prepared the option of using the validation (from menu Data). The
validation is choosing from list (August, September, October, et) and
everything is ok. But I would like to have possibility of choosing all
months, I would like to choose all records and I do not know how to do it.
I
hope that you can help me with it.

Jacek