condition mean min max ZT0-3 20.55 20.55 20.55 ZT4-7 43.1 43.1 43.1 ZT8-11 6.5 6.5 6.5 ZT12-15 21.4 21.4 21.4 ZT16-19 20.6 20.6 20.6 ZT20-23 17.6 17.6 17.6