condition mean min max ZT0-3 2.9122925 2.62547 3.199115 ZT4-7 2.48598 2.48598 2.48598 ZT8-11 1.9009900000000002 1.9009900000000002 1.9009900000000002 ZT12-15 0 0 0 ZT16-19 2.0265750000000002 2.0265750000000002 2.0265750000000002 ZT20-23 3.106775 3.106775 3.106775