condition mean min max ZT0-3 6.3575625 6.145875 6.56925 ZT4-7 8.873864999999999 8.873864999999999 8.873864999999999 ZT8-11 6.822015 6.822015 6.822015 ZT12-15 0 0 0 ZT16-19 9.87916 9.87916 9.87916 ZT20-23 7.6096900000000005 7.6096900000000005 7.6096900000000005