Remove straight due to gaps in data form area chart?

[Infidti]

Is there a simple way to remove this straight line in an area chart i believe its due to gaps in data so the data may exist in 1 point in time disappear then re appear late in the time periods. It seems when there are gaps it creates a straight line to the next data point;

is there a simple way to get rid of this?

[lbendlin]

It may also be caused by sampling because you may have too many data points.