condition mean min max ZT0-3 8.0070500955 7.534570007 8.479530184 ZT4-7 4.83676664975 3.848784439 5.8247488605 ZT8-11 4.4203792467500005 3.4192773455000003 5.421481148 ZT12-15 3.735700004 2.512659051 4.958740957 ZT16-19 3.0904622039999996 2.7831749839999995 3.397749424 ZT20-23 3.29473542875 3.0086996315 3.580771226