condition mean min max ZT0-3 2.8929875000000003 2.67985 3.106125 ZT4-7 3.8797900000000003 3.8797900000000003 3.8797900000000003 ZT8-11 4.088805 4.088805 4.088805 ZT12-15 0 0 0 ZT16-19 7.2539750000000005 7.2539750000000005 7.2539750000000005 ZT20-23 4.56692 4.56692 4.56692