Excell 2007 multiple pasting

Hello,
In Excell, I want to copy the same line several times within the document making slight changes after pasting each line.
A change made in the first pasted line removes the original copied line from the Office Clipboard, requiring the original line to be recopied before pasting to another location.
Every "help" I've read indicates that anything copied remains in the "Clipboard" for repeated pasting until another item is copied or until "enter" is pressed.
I previously used Word Perfect Quattro Pro and there was no problem.
Am I missing a step?