condition mean min max ZT0-3 7.5237533333333335 7.22769 8.101985 ZT4-7 7.95928 7.95928 7.95928 ZT8-11 4.82316 4.82316 4.82316 ZT12-15 6.311014999999999 5.41299 7.20904 ZT16-19 6.85045 6.85045 6.85045 ZT20-23 8.793875 8.793875 8.793875