Dos and Don’ts of Data Visualisation

Do use direct labelling wherever possible, avoiding indirect look-up

If possible, label lines individually and avoid legends.

You want to allow instant identification of the lines but looking them up in a legend takes way too much time. Often the legend is below the chart and its elements are in arbitrary order. Instead, place the labels close to the lines.

However, placing a label next to a line could become an issue when multiple lines end at the same point. In that case, place a legend below the chart.