condition mean min max ZT0-3 9.838414 9.838414 9.838414 ZT4-7 9.3862605 9.3862605 9.3862605 ZT8-11 8.3084915 8.3084915 8.3084915 ZT12-15 8.938280500000001 8.938280500000001 8.938280500000001 ZT16-19 7.1361930000000005 7.1361930000000005 7.1361930000000005 ZT20-23 8.2095555 8.2095555 8.2095555