condition mean min max ZT0-3 12.1051 12.1051 12.1051 ZT4-7 5.576635 5.576635 5.576635 ZT8-11 9.611925 9.611925 9.611925 ZT12-15 16.0479 16.0479 16.0479 ZT16-19 23.441899999999997 23.441899999999997 23.441899999999997 ZT20-23 18.1282 18.1282 18.1282