condition mean min max ZT0-3 3.0317325 2.94902 3.114445 ZT4-7 1.92424 1.92424 1.92424 ZT8-11 3.5547500000000003 3.5547500000000003 3.5547500000000003 ZT12-15 0 0 0 ZT16-19 3.439225 3.439225 3.439225 ZT20-23 2.597295 2.597295 2.597295