The VMware Knowledge Base provides support solutions, error messages and troubleshooting guides
Exported Excel Data Charts Show Different Values Than the Data Charts Within VirtualCenter Client (1828)
There is no workaround available, but you can fix the problem by upgrading to VirtualCenter 1.3 or later.
Request a Product Feature
To request a new product feature or to provide feedback on a VMware product, please visit the Request a Product Feature page.