What is the mean round number for center position when the pick number is less than 23?
CREATE TABLE table_name_39 (round INTEGER, position VARCHAR, pick__number VARCHAR)
SELECT AVG(round) FROM table_name_39 WHERE position = "center" AND pick__number < 23
### Context: CREATE TABLE table_name_39 (round INTEGER, position VARCHAR, pick__number VARCHAR) ### Question: What is the mean round number for center position when the pick number is less than 23? ### Answer: SELECT AVG(round) FROM table_name_39 WHERE position = "center" AND pick__number < 23