I have an issue with historical area charts with two given options for “Missing and NULL values”:

  1. Convert to 0 and display in chart

Shows ugly dashes for values that have a zero:

  1. Do not display in chart

Shows weird straight lines from the beginning to the first occurence of data:

Is there a way to show the values but hide the dashes? The existing options are quite ugly.

Those aren’t dashes. They are the error bars for your chart. Disable the error bars and the dashes will disappear also.