condition mean min max ZT0-3 9.138912 9.138912 9.138912 ZT4-7 9.523490500000001 9.523490500000001 9.523490500000001 ZT8-11 9.002031 9.002031 9.002031 ZT12-15 8.1789925 8.1789925 8.1789925 ZT16-19 9.946183999999999 9.946183999999999 9.946183999999999 ZT20-23 11.6691295 11.6691295 11.6691295