condition mean min max ZT0-3 168.616672 168.616672 168.616672 ZT4-7 179.946628 179.946628 179.946628 ZT8-11 188.0012875 188.0012875 188.0012875 ZT12-15 168.43638249999998 168.43638249999998 168.43638249999998 ZT16-19 162.72284 162.72284 162.72284 ZT20-23 149.99135 149.99135 149.99135