I think VT is meant to be D in 1980.
ND 1980 has the highest trend outside of states not gaining or losing a home state candidate. Also, it's the only state (aside from home state candidates) to appear on this list twice in subsequent elections. Any explanation?
Arkansas is listed 3 times and none of them were subsequent.
Fixed, thanks for pointing that out, and double thanks for being polite about it. And yeah, AR and ND stood out to me as well.
The other thing I noticed from this exercise was the absolutely massive trends in the South in 1976; I had known about them before, but this made me truly appreciate just how large they were. GA trended 59 points to go from 75R-25D in 1972 to 67D-33R in 1976, 10 other Southern states (by census region) trended at least 15 points towards Democrats, and the remaining Southern states (plus MO+KS) trended towards Democrats as well.
Also, if anyone is curious, the largest trend I found was in 1896, when Colorado trended 119.5 points towards Democrats. However, this is kind of a technicality; the Populist nominee won Colorado with 54% of the vote in 1892 when Cleveland wasn't on the ballot, while in 1896 Bryan (who was nominated by both the Democratic and Populist parties) won CO with 71% of the vote in 1896.