condition mean min max ZT0-3 4.03492865 3.625238655 4.444618645 ZT4-7 4.60261091275 4.0919003395 5.113321486 ZT8-11 4.70382576125 4.508683128 4.898968394500001 ZT12-15 5.2192673329999995 4.866863484 5.571671182 ZT16-19 7.041549542499999 6.5366757815 7.546423303499999 ZT20-23 9.486435288 9.199978244499999 9.7728923315