condition mean min max ZT0-3 6.4729944999999995 5.581536272999999 7.364452727 ZT4-7 6.672528970249999 5.536515161 7.8085427795 ZT8-11 8.715592207 7.7560625455 9.6751218685 ZT12-15 9.754681503250001 9.0800007515 10.429362255000001 ZT16-19 7.23746199975 7.111312247500001 7.363611752 ZT20-23 7.2502236295 6.3915074865 8.1089397725