condition mean min max ZT0-3 7.287733333333333 5.49775 10.193439999999999 ZT4-7 5.38095 5.38095 5.38095 ZT8-11 6.237489999999999 6.237489999999999 6.237489999999999 ZT12-15 8.9615075 8.264215 9.6588 ZT16-19 7.752515 7.752515 7.752515 ZT20-23 10.84593 10.84593 10.84593