condition mean min max ZT0-3 26.0036 26.0036 26.0036 ZT4-7 23.113999999999997 23.113999999999997 23.113999999999997 ZT8-11 16.0666 16.0666 16.0666 ZT12-15 19.430799999999998 19.430799999999998 19.430799999999998 ZT16-19 23.939033333333334 23.939033333333334 23.939033333333334 ZT20-23 27.072 27.072 27.072