What is the mean round number center position when pick number less than 23?
Round Pick # Overall Name Position College
Atlanta Falcons draft history
15198842
real real real text text text
2-15198842-47
2 23 55 Peter Konz Center Wisconsin
3 28 91 Lamar Holmes Offensive Tackle Southern Miss
5 23 158 Bradie Ewing Fullback Wisconsin
5 29 164 Jonathan Massaquoi Linebacker Troy
6 22 192 Charles Mitchell Safety Mississippi State
7 42 249 Travian Robertson Defensive Tackle South Carolina
SELECT AVG Round FROM table WHERE Position = center AND Pick # < 23
center 23