Was Bob Gibson even better in 1970 than he was in 1968?

I have written about this before. See Explaining Bob Gibson’s 1968 Season.

In the table below we can see that his FIP ERA as a percentage of the league average was lower in 1970 than in 1968 (1967 and 1969 were not far behind). Also, his lowest FIP- ERA (which takes park effects into account, from Fangraphs) was in 1970. The 61 in 1970 means that his FIP ERA was 61% of the league average.

Year	FIP	Lg FIP	%	FIP-
1959	3.55	3.87	0.917	87
1960	3.68	3.64	1.011	95
1961	3.58	3.94	0.909	85
1962	3.02	3.84	0.786	73
1963	3.13	3.27	0.957	89
1964	3.02	3.39	0.891	83
1965	3.33	3.42	0.974	90
1966	2.76	3.49	0.791	80
1967	2.34	3.26	0.718	73
1968	1.77	2.83	0.625	65
1969	2.30	3.45	0.667	68
1970	2.29	3.84	0.596	61
1971	2.70	3.38	0.799	80
1972	2.54	3.33	0.763	77
1973	2.83	3.69	0.767	77
1974	4.17	3.62	1.152	118
1975	4.50	3.60	1.250	128

 
Gibson is famous for his 1.12 ERA in 1968, but there was alot more offense in 1969 and 1970. So context matters.

On thing that helped him in 1968 was his very low BABIP.

In 1968, Gibson's BABIP was .230, 34 points below what it was for the entire Cardinal staff. That was the farthest below the rest of the staff he was in his career.

In 1969 and 1970, he was actually .002 and .005 above the entire staff. In 1967, he was .012 higher.

I also broke down his performance into RISP and non-RISP situations to try to understand how his ERA could have been so low. He allowed a batting average of .184 overall in 1968 but just .141 with RISP (and .193 in non-RISP situations).  His career average allowed overall was .228 while with RISP it was .219. Those two are pretty close, indicating that Gibson probably did not have any special ability with RISP. He just happened to do very well in those situations in 1968.