condition mean min max ZT0-3 2.1822496045 1.441856057 2.922643152 ZT4-7 3.389029358 2.988170352 3.7898883640000003 ZT8-11 5.118281808166667 4.744983529 5.491580087333333 ZT12-15 5.8194849765 5.327099721 6.3118702319999995 ZT16-19 6.8152708735 6.471433664 7.1591080830000005 ZT20-23 5.200076512666667 4.522250806 5.8779022193333335