condition mean min max ZT0-3 16.9226 16.9226 16.9226 ZT4-7 7.359999999999999 7.359999999999999 7.359999999999999 ZT8-11 15.048650000000002 15.048650000000002 15.048650000000002 ZT12-15 17.01515 17.01515 17.01515 ZT16-19 23.14875 23.14875 23.14875 ZT20-23 25.5417 25.5417 25.5417