condition mean min max ZT0-3 8.05951621925 6.717826840500001 9.401205597999999 ZT4-7 3.346882192 2.9941939134999997 3.6995704705000003 ZT8-11 3.5916433724999997 3.129512244 4.0537745009999995 ZT12-15 8.78888204 6.874955912 10.702808168 ZT16-19 9.025996881249998 8.4542130015 9.597780761 ZT20-23 11.012208277500001 10.545885065 11.47853149