condition mean min max ZT0-3 20.7 20.7 20.7 ZT4-7 11.7 11.7 11.7 ZT8-11 21.35 21.35 21.35 ZT12-15 34.35 34.35 34.35 ZT16-19 52.05 52.05 52.05 ZT20-23 45.2 45.2 45.2