condition mean min max ZT0-3 12.450000000000001 12.450000000000001 12.450000000000001 ZT4-7 4.6 4.6 4.6 ZT8-11 8.95 8.95 8.95 ZT12-15 25.15 25.15 25.15 ZT16-19 20.65 20.65 20.65 ZT20-23 5.3 5.3 5.3