Nathan Roseberry writes:
I thought I had read on your blog that bar charts should always include zero on the scale, but a search of your blog (or google) didn’t return what I was looking for. Is it considered a best practice to always include zero on the axis for bar charts? Has this been written in a book?
The idea is that the area of the bar represents “how many” or “how much.” The bar has to go down to 0 for that to work. You don’t have to have your y-axis go to zero, but if you want the axis to go anywhere else, don’t use a bar graph, use a line graph. Usually line graphs are better anyway.
I’m sure this is all in a book somewhere.