condition mean min max ZT0-3 9.05 9.05 9.05 ZT4-7 13.8 13.8 13.8 ZT8-11 27.1 27.1 27.1 ZT12-15 7.800000000000001 7.800000000000001 7.800000000000001 ZT16-19 15.35 15.35 15.35 ZT20-23 11.7 11.7 11.7