condition mean min max ZT0-3 9.701863333333334 8.7352 11.285685 ZT4-7 9.74105 9.74105 9.74105 ZT8-11 9.3194 9.3194 9.3194 ZT12-15 10.2736225 8.77316 11.774085 ZT16-19 9.345875 9.345875 9.345875 ZT20-23 8.81746 8.81746 8.81746