condition mean min max ZT0-3 2.5804025 2.5354650000000003 2.62534 ZT4-7 3.368545 3.368545 3.368545 ZT8-11 6.418615 6.418615 6.418615 ZT12-15 0 0 0 ZT16-19 5.03562 5.03562 5.03562 ZT20-23 4.0910150000000005 4.0910150000000005 4.0910150000000005