condition mean min max ZT0-3 12.53105 11.4905 13.5716 ZT4-7 8.325759999999999 8.325759999999999 8.325759999999999 ZT8-11 6.321505 6.321505 6.321505 ZT12-15 0 0 0 ZT16-19 7.825394999999999 7.825394999999999 7.825394999999999 ZT20-23 9.12556 9.12556 9.12556