condition mean min max ZT0-3 4.895205 4.22537 5.56504 ZT4-7 4.319725 4.319725 4.319725 ZT8-11 5.681 5.681 5.681 ZT12-15 0 0 0 ZT16-19 7.625805 7.625805 7.625805 ZT20-23 4.7499 4.7499 4.7499