condition mean min max ZT0-3 2.6641325 2.619435 2.70883 ZT4-7 4.016725 4.016725 4.016725 ZT8-11 2.845205 2.845205 2.845205 ZT12-15 0 0 0 ZT16-19 2.4544449999999998 2.4544449999999998 2.4544449999999998 ZT20-23 2.8623950000000002 2.8623950000000002 2.8623950000000002