Question: In what year did the NBS revisit the DOT's 1975 study and find traffic fatalities unaffected?
Sentence: In 1975 the US DOT conservatively identified a 0.7% reduction in traffic fatalities during DST, and estimated the real reduction at 1.5% to 2%, but the 1976 NBS review of the DOT study found no differences in traffic fatalities.
Answer in sentence: yes