Confirmed reports at a Google AdWords Help thread show that if you use the XML format for Google AdWords reports, you will be missing decimal values in the report.

The advertiser who reported this noticed the discrepancy when he generate duplicate reports, one in Excel format and one is XML format. The advertiser said:

AdWordsPro Stephen confirmed the issue and said he will follow up on why this is the case and let us know if it is a bug or a ‘feature.’

Forum discussion at Google AdWords Help.