Nashbar moustache bar clamp dia = 25.4 mm

EF Schwinn Continental randonneur (sp?) bar clam dia = about 63/64 inches by my manual calipers ... 25.00 mm. Since these bikes were produced in their bazillions, I'm going to assume that this is not the obsolete French 25 mm standard, but the 25.4 measured with error. Anyway, what's 4/10 of a mm between friends? (cognoscenti please correct)