condition mean min max ZT0-3 6.76633275975 6.651494555 6.881170964500001 ZT4-7 2.740903072 2.563509376 2.9182967680000003 ZT8-11 3.06713583325 2.177008737 3.9572629295000006 ZT12-15 3.876675843 3.845510191 3.9078414950000004 ZT16-19 3.6226728987500003 3.0164725700000004 4.2288732275 ZT20-23 6.866512199500001 6.058985415 7.674038984000001