Units of measurement are determined by the report's Measure Units property. It defines the basic measurement unit for all the unit-related properties of the report and its elements (such as location, size, border width, etc.). It is set to one hundredth of an inch by default.

If required, the user can change the units to a tenth of a millimeter, by setting the Measure Units property, either using the Property Grid:

... or via the report's Smart Tag: