condition mean min max ZT0-3 14.867715124999998 12.25300347 17.482426779999997 ZT4-7 18.927185455 15.80977914 22.04459177 ZT8-11 19.835708255 19.005726645 20.665689864999997 ZT12-15 18.504315015000003 17.942816020000002 19.06581401 ZT16-19 24.3789930525 21.575491550000002 27.182494554999998 ZT20-23 32.4663719225 31.511023220000002 33.421720625