I saw this chart on Business Insider recently:

Businessinsider_dj_2018-02-07

This links to Market Insider, where there is a tool to make different types of charts. Despite the huge drop depicted above, by last week, the Dow Jones index has recovered to the level at the start of 2018:

Marketinsider_dj_line

The same chart can be made as an area chart (called a "mountain chart" by Market Insider).

Marketinsider_dj_area

The painting of the area serves no purpose here because the area doesn't mean anything.

Imagine adding an inch of space to the bottom of each chart. The area chart is sensitive to the choice of the minimum value of the vertical axis while the line chart isn't. Since the data did not change, it's not a good idea for the display to shift perception. That's why I prefer the line chart.

Tags:
junkcharts
http://junkcharts.typepad.com/junk_charts/

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