The 'Sixth Year Curse' is also an alternate name for the 'Second Term' curse, so you have a point.
For reference, because I did this for a TL test, election years would be: 1920, 1926, 1932, 1938, 1944, 1950, 1956, 1962, 1968, 1974, 1980, 1986, 1992, 1998, 2004, 2010, 2016, 2022.