condition mean min max ZT0-3 7.419545 6.14467 8.694420000000001 ZT4-7 2.66764 2.66764 2.66764 ZT8-11 3.23087 3.23087 3.23087 ZT12-15 0 0 0 ZT16-19 7.3546499999999995 7.3546499999999995 7.3546499999999995 ZT20-23 5.80719 5.80719 5.80719