mode

select mode(yearID) AS value
from baseballStats 
WHERE AtBatting != 0 AND yearID > 2001

select mode(yearID, 'AVG') AS value
from baseballStats 
WHERE AtBatting != 0 AND yearID > 2001

select mode(yearID, 'MIN') AS value
from baseballStats 
WHERE AtBatting != 0 AND yearID > 2001

select mode(yearID, 'MAX') AS value
from baseballStats 
WHERE AtBatting != 0 AND yearID > 2001