Colors and scales break the seam between charts

When reader Chris P. sent in the Mint infographic (discussed here), he pointed out a flaw in the poster.

Look at the legend for the first chart, which is a map of median household incomes.

Now, look at the legend for the second chart, which is the multiple bar chart we discussed before.

Six colors in one, 7 colors in the other.

Lowest bucket is under $40,000 in one, under $25,000 in the other. But both are given the same light yellow color. 

By varying the color scale, the designer completely severs the relationship between the two charts. Worse, a non-existent correlation is invented via common colors that signify nothing!

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If you haven't already, see my other post about this infographic. 

Comments

[Chris]

The map shows median household income, while the chart shows income distribution -- two different things. The range of values in the map is from <40k to >60k, while the range in the chart is zero to 200k+. Makes perfect sense to me, although clearly having the map and chart show slightly different but very similar indicators does invite confusion -- I wonder if there is a better way the designer could have made the distinction clear? Two totally different color scales, perhaps? Although that would most likely break the overall aesthetic unity...