condition mean min max ZT0-3 9.707831 9.707831 9.707831 ZT4-7 8.997977500000001 8.997977500000001 8.997977500000001 ZT8-11 9.179255 9.179255 9.179255 ZT12-15 7.6725555 7.6725555 7.6725555 ZT16-19 7.866954 7.866954 7.866954 ZT20-23 8.612694 8.612694 8.612694