condition mean min max ZT0-3 6.941713333333333 5.99755 7.909895 ZT4-7 5.508464999999999 5.508464999999999 5.508464999999999 ZT8-11 5.296715000000001 5.296715000000001 5.296715000000001 ZT12-15 8.7839375 7.47969 10.088185 ZT16-19 7.33638 7.33638 7.33638 ZT20-23 6.6485 6.6485 6.6485