It is however very rare that absolute differences matter; and even when they do, the scale should (often) be fixed. For example the temperatures: [A: 27.0, B:

It is however very rare that absolute differences matter; and even when they do, the scale should (often) be fixed. For example the temperatures: [A: 27.0, B: 29.0, C: 28.0] versus: [A: 27.0, B: 27.2, C: 26.9] If scale is fit to the min and max values, the charts will look the same. Still, as a rule of thumb, when Y axis doesn't start at 0, the chart is probably misleading. It is very rare that the absolute size of the measured quantity doesn't matter.