condition mean min max ZT0-3 15.403450000000001 15.403450000000001 15.403450000000001 ZT4-7 15.39075 15.39075 15.39075 ZT8-11 7.81318 7.81318 7.81318 ZT12-15 8.110195000000001 8.110195000000001 8.110195000000001 ZT16-19 12.7178 12.7178 12.7178 ZT20-23 14.5794 14.5794 14.5794