condition mean min max ZT0-3 22.44285 20.70595 24.17975 ZT4-7 19.1774 19.1774 19.1774 ZT8-11 19.029600000000002 19.029600000000002 19.029600000000002 ZT12-15 0 0 0 ZT16-19 21.13205 21.13205 21.13205 ZT20-23 25.7038 25.7038 25.7038