condition mean min max ZT0-3 6.5808855610000005 5.130503039 8.031268083 ZT4-7 6.91871135925 6.903428508499999 6.93399421 ZT8-11 6.870228988499999 5.8723471924999995 7.868110784499999 ZT12-15 6.6238519535 6.3054356325 6.9422682745 ZT16-19 8.647526548 7.7300639945 9.5649891015 ZT20-23 14.60522778 13.28673077 15.92372479