condition mean min max ZT0-3 8.927785 8.927785 8.927785 ZT4-7 5.400945 5.400945 5.400945 ZT8-11 4.651045 4.651045 4.651045 ZT12-15 3.938955 3.938955 3.938955 ZT16-19 6.655125 6.655125 6.655125 ZT20-23 8.495330000000001 8.495330000000001 8.495330000000001