Warnings in Numbers?

I was exporting a spreadsheet to excel, then I get a warning, saying that graphs might be inaccurate. When I sent the spreadsheet to my professor. She said it turned out kinda of skewed.


Whats the deal?

What should I do?

so, you have numbers and you were exporting it to an .xls file?

i wonder if you downloaded neooffice, if it might give you a better picture of what an excel user might see when opening the file.