condition mean min max ZT0-3 17.9 17.9 17.9 ZT4-7 5.8 5.8 5.8 ZT8-11 44.099999999999994 44.099999999999994 44.099999999999994 ZT12-15 23.65 23.65 23.65 ZT16-19 15.350000000000001 15.350000000000001 15.350000000000001 ZT20-23 16.95 16.95 16.95