condition mean min max ZT0-3 3.5456390064999996 3.010624965 4.080653047999999 ZT4-7 3.58067568975 3.4015668605 3.759784519 ZT8-11 3.0975665505 2.9855816335 3.2095514675 ZT12-15 3.0826290802500003 2.8710462850000003 3.2942118755000003 ZT16-19 5.07622431425 3.7694379959999997 6.3830106325 ZT20-23 9.423651734500002 8.6038883375 10.2434151315