condition mean min max ZT0-3 6.117248333333333 4.8529800000000005 7.35863 ZT4-7 4.50666 4.50666 4.50666 ZT8-11 5.163625 5.163625 5.163625 ZT12-15 8.91778 8.136425 9.699135 ZT16-19 9.011579999999999 9.011579999999999 9.011579999999999 ZT20-23 8.963585 8.963585 8.963585