condition mean min max ZT0-3 10.9156325 10.5673 11.263964999999999 ZT4-7 5.71305 5.71305 5.71305 ZT8-11 11.5136 11.5136 11.5136 ZT12-15 0 0 0 ZT16-19 16.22265 16.22265 16.22265 ZT20-23 13.40175 13.40175 13.40175