condition mean min max ZT0-3 220.287511 220.287511 220.287511 ZT4-7 533.2334834999999 533.2334834999999 533.2334834999999 ZT8-11 326.94321249999996 326.94321249999996 326.94321249999996 ZT12-15 200.919566 200.919566 200.919566 ZT16-19 150.9514825 150.9514825 150.9514825 ZT20-23 161.076844 161.076844 161.076844