condition mean min max ZT0-3 9.112778333333333 8.13796 10.7011 ZT4-7 8.80687 8.80687 8.80687 ZT8-11 7.517645 7.517645 7.517645 ZT12-15 8.2438 7.716850000000001 8.77075 ZT16-19 6.650125 6.650125 6.650125 ZT20-23 10.975405 10.975405 10.975405