According to Wikipedia, NYC MTA has 11,574,566 riders every week day, or 3,009,387,160 riders every year, not including weekends.
That works out to about $.11 per ride, or $.22 per day per person assuming an average of two trips per day.
If they raise the price of passes $5.00 and single ride fares $.11, they should have enough to make up the shortage.