Brandon Nimmo had an on-base percentage of .362 when leading off a game in his career.

brandon nimmo obp in leadoff spot
Interpreted as:
Brandon Nimmo obp in leadoff spot in his career
Brandon NimmoBrandon Nimmo370.36237031882262774309990013335.258.418.780
StatMuse has event-level data for on-base percentage going back to the 1974 season.
Some of the information used here was obtained free of charge from Retrosheet.