condition mean min max ZT0-3 5.6717949999999995 5.6717949999999995 5.6717949999999995 ZT4-7 4.26977 4.26977 4.26977 ZT8-11 4.72941 4.72941 4.72941 ZT12-15 4.249385 4.249385 4.249385 ZT16-19 5.27708 5.27708 5.27708 ZT20-23 4.96544 4.96544 4.96544