condition mean min max ZT0-3 30.984898 30.984898 30.984898 ZT4-7 25.64286 25.64286 25.64286 ZT8-11 25.2714305 25.2714305 25.2714305 ZT12-15 20.14677 20.14677 20.14677 ZT16-19 33.541007 33.541007 33.541007 ZT20-23 30.173185500000002 30.173185500000002 30.173185500000002