The burn rate on road construction has exceeded the collection rate for gas taxes for some time now. This month the savings built up in the past are running out, and the Feds are cutting smaller, pro-rated checks, with a promise to pay back the difference "in the future". This will mean many states without savings of their own - which I suspect includes Kentucky, but not Indiana - will have to curtail road construction.

Source: http://www.nytimes.com/2008/09/06/us/06highway.html?_r=1&hp&oref=slogin