Problem with green tips on the excel sheet(errors)

Hello, i am importing data from a datatable in to excel, i am seeing all the data in the excel but with green tips to each cells. what may be problem and how can we avoid this green tips all over the sheet. i have observed these green tips only to the numbers i displayed but not to the string/text i displayed.
It is irritationg to look at when i open the report.Please help in this regard.
Regards,
Sravan

Please check if those numbers is string in your datatable.