condition mean min max ZT0-3 3.2741775 2.6290050000000003 3.9193499999999997 ZT4-7 6.168085 6.168085 6.168085 ZT8-11 17.1802 17.1802 17.1802 ZT12-15 0 0 0 ZT16-19 11.0988 11.0988 11.0988 ZT20-23 7.8457799999999995 7.8457799999999995 7.8457799999999995