condition mean min max ZT0-3 12.752500000000001 12.752500000000001 12.752500000000001 ZT4-7 8.92504 8.92504 8.92504 ZT8-11 5.5779250000000005 5.5779250000000005 5.5779250000000005 ZT12-15 6.63042 6.63042 6.63042 ZT16-19 13.99535 13.99535 13.99535 ZT20-23 15.93535 15.93535 15.93535