The reports are run monthly. Even if you wanted to run one on a shorter time period, since last year's numbers were run for the whole month, you have nothing to compare them with.
And you forget that some people still do purchase their tickets on board. Those numbers are calculated manually, on a monthly basis as well.
That said, don't be surprised if there's little or no spike in ridership. The price of gas shocked us all last week when it shot up, but people get used to these things real quick. Those who prefer to use a car will continue to use their car.
Jim