This is "correct" behavior for an area chart, the display style you have chosen. Think of the display as a stacked bar chart with lines drawn between the bars.
Look at the data point for 2016 on your first screen. There is no blue plotted on the 2016 point because the 2016 value is zero. This is correct.
Due to the display drawing a line connecting 2013 and 2016, it sort of makes it look like there are values in the middle.
An area chart is probably not a good choice of style for this data.
Rob, by unchecking "suppress zero values" the chart changed to looking like this:
Note that the values at 2014 went away (which is how it should display) but it still populated everything from 2014 to 2016.
If there is no way to to shade in underneath the lines on my chart would there be a way to force 0 values for everything if the values are null?
For instance in my data I have a year and a value in each record. The light blue section here only has records for 2013 and 2014 and consequently only has values for those. Would I be able to force 0 values for the other years (without messing up the scale on the graph?)
Thank you for all of your help! I am pleased to say that this issue is solved!
This was solved by concatenating a new table which replicated the original data values for the relevant fields but loaded in "0" values for the "amount" field.
For example: The light blue portion of the graph now has 0 values loaded in for years 2015 and 2016 which causes it to taper to 0 after 2014 as opposed to connecting the line from 2015 to 2016 where there previously were no values.
Rob, I appreciate all of your help and stacked bar charts would have been a great solution, however using the stacked line chart was a business requirement.