How many of the 47% have been income tax payers over the last few years

[rob in cal]

    Another interesting aspect of Romneys comments about the 47% who pay no federal income tax (and lets give him some credit for saying federal income tax, and not federal taxes in general), is that I would guess that a fair percentage of that 47% have paid income tax over the last years.
   Some may have recently retired, some have taken pay cuts and some may just be working less and hence making less money of late.  Personally I know that in tax year 2012 in fact I will be paying federal income tax, but over the last few years haven't, due to two minor children.  As my business income grows and my daughter is going to be 18 in a few years, I'd bet that over the next years I will in fact fall into the 53% some of those years. 
    Anyway, to argue that there is some permanent, entrenched 47% group who year in year out don't pay income tax, and thats the impression I got from hearing Romney speak, shows a disturbing lack of faith in American economic mobility that I'd think that a Republican candidate would not share.