condition mean min max ZT0-3 54.012425 51.1826 56.84225 ZT4-7 25.21515 25.21515 25.21515 ZT8-11 11.4161 11.4161 11.4161 ZT12-15 0 0 0 ZT16-19 21.18235 21.18235 21.18235 ZT20-23 40.91185 40.91185 40.91185