Hi James,<?xml:namespace prefix = o ns = "urn:schemas-microsoft-com:office:office" />
Thank you for considering Aspose.
You may use Style.Number = 9 for percentage display value. Please see the following sample code for your reference:
//Instantiating a Workbook object
Workbook workbook = new Workbook();
//Obtaining the reference of the newly added worksheet by passing its sheet index
Worksheet worksheet = workbook.Worksheets[0];
//Adding a numeric value to "A1" cell
worksheet.Cells["A1"].PutValue(0.12);
//Setting the display format of the value to number 9 to show value as percentage
worksheet.Cells["A1"].Style.Number = 9;
//Saving the Excel file
workbook.Save("D:\\Test_Temp\\book2.xls", FileFormatType.Default);
Please check the following documentation link for further details regarding display formats:
http://www.aspose.com/documentation/.net-components/aspose.cells-for-.net/setting-display-formats-of-numbers-dates.html
Thank You & Best Regards,