In 1998 NASA published a graph showing 1934 as the hottest year on record. NASA’s more recent graphs have dropped temps for 1934 by more than one degree Fahrenheit

Data analyst Tony Heller frequently compares current government temp charts with charts published by the same government agencies in the past.

Heller notes that “In 1998, NASA showed 1934 as the hottest year on record in the US, and declining temperatures for the rest of the century. They have since rewritten the data to eliminate the post 1930s cooling. 1998 used to be one degree Fahrenheit cooler than 1934, and now it is warmer.”

See here.