condition mean min max ZT0-3 30.294557 30.294557 30.294557 ZT4-7 28.569768500000002 28.569768500000002 28.569768500000002 ZT8-11 22.807477499999997 22.807477499999997 22.807477499999997 ZT12-15 29.296787000000002 29.296787000000002 29.296787000000002 ZT16-19 17.241443500000003 17.241443500000003 17.241443500000003 ZT20-23 16.327638999999998 16.327638999999998 16.327638999999998