condition mean min max ZT0-3 30.450000000000003 30.450000000000003 30.450000000000003 ZT4-7 25.5 25.5 25.5 ZT8-11 15.75 15.75 15.75 ZT12-15 13.8 13.8 13.8 ZT16-19 32.349999999999994 32.349999999999994 32.349999999999994 ZT20-23 19.650000000000002 19.650000000000002 19.650000000000002