condition mean min max ZT0-3 5.2065383333333335 4.63584 5.787455 ZT4-7 4.186965 4.186965 4.186965 ZT8-11 4.206855 4.206855 4.206855 ZT12-15 6.6159575 5.73549 7.496425 ZT16-19 4.588509999999999 4.588509999999999 4.588509999999999 ZT20-23 4.820415000000001 4.820415000000001 4.820415000000001