Line Charts are usually used for showing continuous changes in the data over a period of time or some trends. The coordinate system is usual: categories are spread along the horizontal X axis and the values shown on the vertical Y axis.
This line chart is completely monochrome. In some cases, we need to print a chart or make it fully accessible by people who have got problems with color perception. In bar, area or column charts hatch fills are used, but we cannot make the same for the Line Charts, as Lines can't be hatch filled. When monochrome line series are only colored with hues of a monochrome palette, the difference between them is not very notable - different types of lines: dashed and solid work much better.
Line charts show the problems of the ACME Corp. during the year. Months, which are categories, are spread along the X axis, the values – a number of unpleasant cases – along the Y axis. The crosshair is enabled; all points of the year selected by the crosshair are being hovered and marked, tooltips are shown for each series separately. The stroke settings for each series are modified, so the Purchase Return series is solid black, the Delivery Failure series is colored in dark gray and stroke is modified so it looks as long dash - short dash; the Order Cancellation series is dashed and in light-grey color.