condition mean min max ZT0-3 0.0 0.0 0.0 ZT4-7 0.0 0.0 0.0 ZT8-11 0.0 0.0 0.0 ZT12-15 0.0 0.0 0.0 ZT16-19 0.06590205883333333 0.053437872 0.07836624566666667 ZT20-23 0.024348082500000003 0.0 0.048696165000000007