condition mean min max ZT0-3 163.860753 163.860753 163.860753 ZT4-7 240.9026385 240.9026385 240.9026385 ZT8-11 304.412724 304.412724 304.412724 ZT12-15 220.960297 220.960297 220.960297 ZT16-19 178.2547845 178.2547845 178.2547845 ZT20-23 179.935915 179.935915 179.935915