condition mean min max ZT0-3 7.46473 4.5660050000000005 10.1969 ZT4-7 4.26914 4.26914 4.26914 ZT8-11 6.46582 6.46582 6.46582 ZT12-15 10.28473 8.56556 12.0039 ZT16-19 6.584095 6.584095 6.584095 ZT20-23 7.96087 7.96087 7.96087