<Li> Interstate 88 in Illinois had previously been designated as Illinois Route 5 . </Li> <Li> 50 miles (80 km) of the Maine Turnpike between Portland and West Gardiner were designated as Interstate 495 in 1988 . The designation for this segment was changed in 2004 to Interstate 95 to simplify the Interstate numbering scheme in Maine . </Li> <P> Congress lifted all federal speed limit controls in the National Highway System Designation Act of 1995, returning all speed limit determination authority to the states effective December 8, 1995 . Several states immediately reverted to already existing laws . For example, most Texas rural limits that were above 55 mph (90 km / h) in 1974 immediately reverted to 70 mph (115 km / h), causing some legal confusion before the new signs were posted . Montana reverted to non-numerical speed limits on most rural highways, although its legislature adopted 75 mph (120 km / h) as a limit in 1999; as a result, according to Insurance Institute for Highway Safety researcher Anne McCartt, "What's impressive is the huge drop in the percent of vehicles going very fast...The proportion of vehicles exceeding 75 mph, the limit set (by Montana) in 1999, tumbled 45 percent . The proportion surpassing 80 mph plummeted 85 percent . Large trucks slowed, too ." (She did not mention that the IIHS survey of traffic speeds on Interstate highways in 2006 she referred to, found Montana, as compared with New Mexico and Nevada, had the highest compliance with the 75 mph speed limit on rural interstates: 76 percent .) Hawaii was the last state to raise its speed limit when, in response to public outcry after an experiment with traffic enforcement cameras in 2002, it raised the maximum speed limit on parts of Interstates H - 1 and H - 3 to 60 mph (95 km / h). </P> <P> Despite the repeal of federal speed limit controls, 2011 maximum speed limits were, on average, lower than in 1974: </P>

When did the speed limit change from 55 to 70 in texas