Currently, Virginia is the only state allowing hybrid vehicles in High Occupancy Vehicle lanes, and the percentage of vehicles in HOV lanes is increasing. The percentage of vehicles in HOV lanes has doubled from the fall of 2003 to spring 2004, from four percent to eight percent, according to an Associated Press report. Of the 6,000 vehicles in the HOV lanes during the morning commute along I-95, about 500 are hybrids. The Federal Highway Administration has ruled the Virginia law violates federal regulations. The Virginia HOV exemption expires July 1, 2006 and it may take an act of Congress to reinstate it. Rep. Darrell Issa, R-Calif., introduced legislation in 2003 to allow states to open HOV lanes to hybrids, but a transportation subcommittee has yet to hold a hearing on the matter. If the HOV incentive runs out, there is concern whether the savings on gas will be enough to keep the popularity of these vehicles high.