condition mean min max ZT0-3 11.51426 5.0062 19.28705 ZT4-7 13.3015 13.3015 13.3015 ZT8-11 10.3022 10.3022 10.3022 ZT12-15 15.1863 12.62485 17.74775 ZT16-19 6.585735000000001 6.585735000000001 6.585735000000001 ZT20-23 22.1493 22.1493 22.1493