condition mean min max ZT0-3 9.565193333333333 6.572235000000001 13.7951 ZT4-7 12.12145 12.12145 12.12145 ZT8-11 2.086265 2.086265 2.086265 ZT12-15 9.179035 8.516645 9.841425000000001 ZT16-19 12.754825 12.754825 12.754825 ZT20-23 16.668100000000003 16.668100000000003 16.668100000000003