condition mean min max ZT0-3 591.232057 591.232057 591.232057 ZT4-7 320.708523 320.708523 320.708523 ZT8-11 306.543417 306.543417 306.543417 ZT12-15 337.1508135 337.1508135 337.1508135 ZT16-19 339.06719499999997 339.06719499999997 339.06719499999997 ZT20-23 308.871043 308.871043 308.871043