condition mean min max ZT0-3 111.46888889 111.46888889 111.46888889 ZT4-7 97.8288889 97.8288889 97.8288889 ZT8-11 98.12111111 98.12111111 98.12111111 ZT12-15 141.3688889 141.3688889 141.3688889 ZT16-19 145.86888889 145.86888889 145.86888889 ZT20-23 134.17999999 134.17999999 134.17999999