condition mean min max ZT0-3 14.087237389999999 12.5897668 15.58470798 ZT4-7 27.738539744999997 16.57204622 38.90503327 ZT8-11 69.2941099075 51.950603825 86.63761599 ZT12-15 38.98778522 17.515494405 60.460076035 ZT16-19 17.386882155000002 15.104627409999999 19.6691369 ZT20-23 13.399677024999999 13.37932292 13.42003113