Excell 2002 version is changing the last number of my credit card accounts to
0!!
Can I be doing something wrong?

I am using Excell 2002. I created a list of my credit cards to keep track of
them, and I just have noticed that in a column that I named credit card
numbers, the last digit is changed to "0" !!!

I customized to accept 16 numbers (####-####-####-####) which follow the
credit card format account numbering. when I enter the numbers say
1111222233334444 I expected to get 1111-2222-3333-4444; however to my
surprise I am getting 1111-2222-3333-4440, and it does not matter that I try
to change it. I will still get the same result. I tried changing the whole
column cell format to just Text or to Number, but I does not help.

Is this a major flow in Microsoft Excell (2002) or am I missing somthing?
I will appreciate any suggestions, Thanks
--
Gabriel