designstorm how-to: dot plots
TRANSCRIPT
Designstorm How-to:
Dot Plots
Edward Tufte would say they’re a better data-to-ink ratio than
side-by-side bars. The way we process information makes it easier
to see the distance of a line than the space between the length of
two bars. And, arguably, not only are these a flat-out better chart
choice for telling some data stories, they look distinctive and can
grab a reader’s attention.
Dot plots aren’t a stock chart type in Excel, so creating them takes
a bit of hacking a scatterplot, but nothing that can’t be
accomplished with a bit of guidance.
Read more on why dots are better than paired columns, or see a quick
play-by-play with ways to develop and format your dot plots.
why dot plots
Use dot plots when you want to emphasize the change
between two points across multiple categories.
Instead of these… Try this!
Format your data in a table, as you would for
your normal column chart. 1.
Add two additional columns of data that you’ll
need to create your dot plot. 2.
“Dot spacing” values
should be equidistant from
one another and will be
used as your y-axis.
“Line size” values
will be used for the
length of your line.
Create the basic framework for your dot plot
using a scatterplot. 3.
Select your first data series
by highlighting your values
+ dot spacing. Use CTRL
to select multiple non-
adjacent cells.
Now you should have a scatterplot that will
be the backbone of your dot plot.
Add your second data series. 4.
Series X values is your next data series
(here, the column for Year 5) and Y values
are your “dot spacing” – only select the
values, not the headers.
Format your markers as circles and increase
the size using “Format Data Series” 5.
Now you should have both markers on the graph,
formatted as large dots on separate lines.
Declutter your chart. 6.
Left click to highlight and then
delete the major gridlines and
the Y axis (which is just our dot
spacing placeholders). Right click the X
axis and select
“Format Axis”;
Change “Major tick
mark” to “None”.
Add the lines connecting your
two data series. 7.
From Chart Tools > Layout >
Analysis > Error Bars, select
“Error Bars with Standard Error”
to create your lines.
Delete the vertical lines created when you
added your standard error bars. 8.
Select and delete
the vertical lines.
Format your horizontal standard error bars
to connect your two dots. 9.
Select the “Line Size” data for
your Positive Error Value.
Leave the Negative Error Value as is.
Your dot plot should look like this now:
two dots, connected by a line.
Add data labels as text boxes (the easiest option for
custom formatting – you can also try an XY labeler macro) 10.
Insert the text boxes from the
Chart Tools ribbon, not the
general “Insert” ribbon – this
way your labels will stay with
your chart if you copy and paste
it to a new file.
Use color purposefully (no rainbow charts!) 11. Here, we use orange to
highlight the final value at the
end of the project.
Add a title that clearly states what your
reader should take away from your chart. 12.
In a report, consider adding data labels. If you do, delete the x axis – it’s duplicative with the labels.
Get creative with formatting to make sure
your key data story stands out!
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