condition mean min max ZT0-3 838.608946 838.608946 838.608946 ZT4-7 419.362242 419.362242 419.362242 ZT8-11 498.296284 498.296284 498.296284 ZT12-15 526.871787 526.871787 526.871787 ZT16-19 1261.3526355 1261.3526355 1261.3526355 ZT20-23 1428.099809 1428.099809 1428.099809