condition mean min max ZT0-3 4.034185 4.034185 4.034185 ZT4-7 3.23621 3.23621 3.23621 ZT8-11 2.146165 2.146165 2.146165 ZT12-15 3.9508 3.9508 3.9508 ZT16-19 4.52183 4.52183 4.52183 ZT20-23 4.442165 4.442165 4.442165