condition mean min max ZT0-3 1.2963399999999998 1.2963399999999998 1.2963399999999998 ZT4-7 0.9176985 0.9176985 0.9176985 ZT8-11 0.6140410000000001 0.6140410000000001 0.6140410000000001 ZT12-15 0.687099 0.687099 0.687099 ZT16-19 1.1438925 1.1438925 1.1438925 ZT20-23 1.57456 1.57456 1.57456