Federal funding for highway and transit systems projects should drop by over $15 billion next year, according to an analysis of transportation spending trends by the Associated General Contractors of America.

The federal government invested $78.6 billion in road and transit construction projects in 2009, including $51 billion in regular federal transportation funding and $27.6 billion in stimulus funding. However, next year's highway funding will be down to $63.4 billion, $9.8 billion of which will come from the remaining stimulus transportation funds, and the rest from regular transportation funding.

According to the association, this 19.3 percent fall in funding will result in over 430,000 layoffs throughout the economy.

"Boosting transportation investments will keep thousands of construction workers employed at a time when our economy can scarcely afford more layoffs," said Stephen Sandherr, the association's CEO. "The success of the stimulus in saving countless construction jobs will have been in vain if its sequel is underinvestment in our roads, bridges and transit systems."

Non-stimulus federal transportation funds are stuck at near current levels because Congress has not passed the six-year surface transportation bill to replace legislation that expired at the end of September.