condition mean min max ZT0-3 3.3487500000000003 3.3487500000000003 3.3487500000000003 ZT4-7 0.6768185 0.6768185 0.6768185 ZT8-11 0.8903605 0.8903605 0.8903605 ZT12-15 1.5953955 1.5953955 1.5953955 ZT16-19 0.432242 0.432242 0.432242 ZT20-23 5.9110949999999995 5.9110949999999995 5.9110949999999995