condition mean min max ZT0-3 0.704628 0.704628 0.704628 ZT4-7 0.3347895 0.3347895 0.3347895 ZT8-11 0.30650049999999995 0.30650049999999995 0.30650049999999995 ZT12-15 0.5112445 0.5112445 0.5112445 ZT16-19 0.512929 0.512929 0.512929 ZT20-23 0.7967995 0.7967995 0.7967995