condition mean min max ZT0-3 0.5908801666666667 0.3538555 0.9661379999999999 ZT4-7 1.1297899999999998 1.1297899999999998 1.1297899999999998 ZT8-11 0.9890540000000001 0.9890540000000001 0.9890540000000001 ZT12-15 0.55021175 0.4674735 0.63295 ZT16-19 1.166064 1.166064 1.166064 ZT20-23 1.2549565 1.2549565 1.2549565