condition mean min max ZT0-3 9.621595 9.621595 9.621595 ZT4-7 10.212420999999999 10.212420999999999 10.212420999999999 ZT8-11 9.313045500000001 9.313045500000001 9.313045500000001 ZT12-15 9.8249625 9.8249625 9.8249625 ZT16-19 9.269808 9.269808 9.269808 ZT20-23 8.869899 8.869899 8.869899