condition mean min max ZT0-3 1474.385903 1474.385903 1474.385903 ZT4-7 1274.9451279999998 1274.9451279999998 1274.9451279999998 ZT8-11 694.3072285000001 694.3072285000001 694.3072285000001 ZT12-15 583.6210135 583.6210135 583.6210135 ZT16-19 421.8906865 421.8906865 421.8906865 ZT20-23 507.127101 507.127101 507.127101