condition mean min max ZT0-3 7.0669925 6.845925 7.28806 ZT4-7 6.6004950000000004 6.6004950000000004 6.6004950000000004 ZT8-11 6.614975 6.614975 6.614975 ZT12-15 0 0 0 ZT16-19 10.128745 10.128745 10.128745 ZT20-23 8.87993 8.87993 8.87993