displaying numbers in excel

[kia cat]

Trying to list store card nos etc in excel 2007, some are 18 digit nos. It's easier to read if the numbers are in blocks of four. Formatted the cell so that I can input them as one string, yet it rounds down the last three numbers. Any ideas ? Thanks

[boxtops]

I don't quite understand what's happening here - I have just opened a new spreadsheet in Excel 2007 and I have the cell formatted to Number/General, and it lets me put all 16 numbers in, and the spaces between each block of 4. Is your formatting different to this?

[kia cat]

boxtops - thanks. It was when I came to an 18 digit one, it rounded down the last three numbers. Not a major problem, I just removed the formatting and keyed in with spaces as I went. Perhaps that's the maximum it'll cope with?

[boxtops]

Not for me - I have tried four groups of 4 and another of 2 and it still saves OK. It saves like that too. Very odd! The Number/General format ought to let you put in as much as you like.

[kia cat]

Boxtops - just tried again, a new sheet formatted cell with 4 blocks of 0000 then two 00
still doing it! Could it be something in excel options?

[ABerrant]

Excel can only handle numerals with 15 significant digits of precision.

[kia cat]

Thanks ABerannt, can't understand why it works for boxtops. I'll live with it!