Pitcher rating and stats

Who were the best, worst and most efficient Pitchers in 2020? Since the end of the 2020 regular season I have been working on some statistical analysis of pitcher’s performance in games. When I first became interested in pesäpallo I was surprised that there weren’t any statistics for pitchers or team’s defence at all. At the time, there was very little in the way of statistics for fielders in baseball or cricket and it was in fact a major talking point amongst MLB fans and commentators. In both cricket and baseball however there has always been a method of calculating a pitcher/bowler’s performance, usually based on the number of runs scored against them measured against the number of batters they faced or innings/overs they played. Pesis didn't seem to have any equivalent, which led me to wonder two things: (1) why are there no statistics? (2) what would the statistics look like if they did exist? Why are there currently no pitching/defence statistics To answer this question,...