condition mean min max ZT0-3 19.847475000000003 16.21515 23.4798 ZT4-7 15.982850000000001 15.982850000000001 15.982850000000001 ZT8-11 15.6776 15.6776 15.6776 ZT12-15 0 0 0 ZT16-19 19.6297 19.6297 19.6297 ZT20-23 19.496650000000002 19.496650000000002 19.496650000000002