Data messing up with negative values in stacked area graph

[vincemat]

Bug report

Codepen

Please look at this codepen.

Explanation

• What is the behavior you expect:
  When removing a serie from the visualisation by clicking on it on the legend, the value of this serie is disapearing but the result data on the graph is wrong.
• What is happening instead:
  If I click on 'west', the graph is showing data for 'north' and 'south' but the graph is not in line anymore with the real data: in 2004 the sum of south (318) and north (-156) is 162 but the graph is showing negative value for the total.

[junedchhipa]

You're right, I confirm the issue and will look into it soon.