Line Charts are usually used for showing continuous changes, like changes in temperature or some kinds of rates. They have usual coordinate system, so x-axis is horizontal and holds the categories while y-axis is vertical and the values are spread along it.
This chart is a simple line chart with three series where are a lot of different features are enabled, making the chart more informative. Three line series are responsible for showing the debt-to-income ratios for three counties in the period of 20 years. DTI is a percentage of a consumer’s monthly gross income that goes for paying debts. The less DTI is the more affordable and recommended it is to buy something (property in those three counties in this sample).
Axis range markers and Axis Text Markers are added to the chart to make it clear when it was wise to buy some property and when it wasn’t. The lowest range, from 0% to 28% demonstrates the most favorable ratio for a deal; the second range from the bottom highlights the ratio range when it was marginally affordable. In the years which are in the third range, from 38% to 48%, it wasn’t really affordable to buy any items of property with a fixed-rate of mortgage, the mortgage became interest-only. When the DTI rate overcame 48%, it was completely unaffordable and profitless to buy property.