By the way, your "risk free interest rate" is actually below inflation. For example, inflation in the US was 1.6% for 2014, while 1 yr US treasury bonds yielded only about 0.25% the same year, so you are obviously dancing upon nothing...
This simply means that the real risk-less interest rate was negative.
Thereby it cannot serve as a proof of what you are trying to prove. If you take a look at historical risk-free rates of short-term treasuries (or other short-term financial assets of the kind, for that matter), you will find plenty of periods where rates have been significantly below inflation in the same period.