condition mean min max ZT0-3 5.864125 5.68405 6.0442 ZT4-7 5.368905 5.368905 5.368905 ZT8-11 4.801905 4.801905 4.801905 ZT12-15 0 0 0 ZT16-19 9.67729 9.67729 9.67729 ZT20-23 9.23961 9.23961 9.23961