condition mean min max ZT0-3 9.266314 9.266314 9.266314 ZT4-7 9.572099 9.572099 9.572099 ZT8-11 8.845348 8.845348 8.845348 ZT12-15 9.3605005 9.3605005 9.3605005 ZT16-19 9.442604 9.442604 9.442604 ZT20-23 8.5899435 8.5899435 8.5899435