condition mean min max ZT0-3 2.482655 2.482655 2.482655 ZT4-7 2.901655 2.901655 2.901655 ZT8-11 4.461485 4.461485 4.461485 ZT12-15 0.95955 0.95955 0.95955 ZT16-19 0.850815 0.850815 0.850815 ZT20-23 3.34753 3.34753 3.34753