condition mean min max ZT0-3 7.1499999999999995 7.1499999999999995 7.1499999999999995 ZT4-7 9.2 9.2 9.2 ZT8-11 9.8 9.8 9.8 ZT12-15 8.85 8.85 8.85 ZT16-19 15.5 15.5 15.5 ZT20-23 9.0 9.0 9.0