condition mean min max ZT0-3 3.7422383333333333 3.07158 4.82553 ZT4-7 7.579475 7.579475 7.579475 ZT8-11 8.076195 8.076195 8.076195 ZT12-15 8.8265975 7.92825 9.724945 ZT16-19 6.40367 6.40367 6.40367 ZT20-23 4.0694 4.0694 4.0694