Conversation so far:
when did the speed limit change from 55 to 70 in texas
The speed limit in Texas increased to 70 mph in December of 1995.
when did the speed limit change from 55 in California
The speed limit in California was last raised in 1995 from 55 to 65 mph on most highways.
why did California and Texas increase their speed limits in 1995
Texas and California increased their speed limit after National Highway Designation Act passed by Congress on November 28, 1995, which officially removed all federal speed limit controls.

Question: what were the effects
Self-contained rewrite: what were the effects on removing federal speed limit controls