condition mean min max ZT0-3 27.695675 25.7953 29.596049999999998 ZT4-7 19.807850000000002 19.807850000000002 19.807850000000002 ZT8-11 4.731965000000001 4.731965000000001 4.731965000000001 ZT12-15 0 0 0 ZT16-19 11.191475 11.191475 11.191475 ZT20-23 28.7339 28.7339 28.7339