I have some NT05 tires from Nitto. 295/45/R18. Nitto's site says 730 revs per mile. http://nittotire.com/#index.tire.nt05.sizes I have a spreadsheet that calculates revs per mile and I also checked it with discount tire's online calculator. They both say 708 revs per mile for this tire size. http://www.discounttiredirect.com/direct/brochure/info/tmpInfoTireMath.jsp What's the problem? And which is the correct value?