condition mean min max ZT0-3 10.050035 6.83995 15.1677 ZT4-7 16.3281 16.3281 16.3281 ZT8-11 7.72223 7.72223 7.72223 ZT12-15 11.247655 11.11892 11.37639 ZT16-19 8.435870000000001 8.435870000000001 8.435870000000001 ZT20-23 12.448550000000001 12.448550000000001 12.448550000000001