condition mean min max ZT0-3 7.7673 7.5265699999999995 8.083755 ZT4-7 10.2998 10.2998 10.2998 ZT8-11 16.9664 16.9664 16.9664 ZT12-15 28.545150000000003 26.024700000000003 31.065600000000003 ZT16-19 18.47635 18.47635 18.47635 ZT20-23 13.65495 13.65495 13.65495