# Intuition / motivation for 2 “measure” values on a bullet chart

I am trying to understand a bit more about the statistical intuition behind bullet charts. This one in particular has two "measure" readouts, one is dark blue one is light blue:

For clarity, the gray shadings that we see are the qualitative measures, often depicting ordinal thresholds (above xx level = good, above yy level = great, ect). The black marker is used as a "marker" to show the value of something (though I suppose it could be repurposed to show other descriptive stats, like median)

## Question

Is there an existing convention regarding how to interpret the existence of two "measure" readouts (dark blue bar, light blue bar)? I concede the point that with visualization the sky is the limit, of course we can depict whatever we want. What I'm after is: what is the motivation, generally speaking, for wanting this kind of granularity in the visualization?

Choose any of the examples: Revenue, profit, order size, new customers, satisfaction if you dont mind a basic worked out example / applied analysis to demonstrate why it would be meaningful to two colors for the inner blue bars.

## Data

[
{"title":"Revenue","subtitle":"US$$, in thousands","ranges":[150,225,300],"measures":[220,270],"markers":[250]}, {"title":"Profit","subtitle":"%","ranges":[20,25,30],"measures":[21,23],"markers":[26]}, {"title":"Order Size","subtitle":"US$$, average","ranges":[350,500,600],"measures":[100,320],"markers":[550]},
{"title":"New Customers","subtitle":"count","ranges":[1400,2000,2500],"measures":[1000,1650],"markers":[2100]},
{"title":"Satisfaction","subtitle":"out of 5","ranges":[3.5,4.25,5],"measures":[3.2,4.7],"markers":[4.4]}
]


I don't know that there is a convention. To make sense in the bullet chart context, we should have:

• dark blue value can never be greater than light blue value
• each value can be interpreted against the thresholds.

The first requirement rules out things like previous-year/current-year. The second rules out part-to-whole uses, such as domestic and foreign parts.

The most reasonable interpretation I can think of is to represent a low/high range to show uncertainty or a summarization of multiple values.