Data Controls :: GridView Export To Excel - Round Decimal Numbers To Two Decimal Places

I was read your post: "Export GridView to Excel in ASP.Net with Formatting using C#" and is very useful. That code works perfect. But I need create a new format for a specific column in my sheet before to export it. For example:My DataTable have a column with decimal numbers and I'm trying reduce the tenths for each number.I want this: 2,874444 ----> 2,87 for a specific range. In this case I need it for all numbers in the column 13 or well said for the Column called N in Excel. Only reduce two tenths.

I used:

xlWorkSheet.Range["N"+h,"N"+h].NumberFormat = "0.00";

And no works (h is for rows, N is the column. Into a foreach).