Bilateral Graph

Bilateral graphs depict increases and decreases on either side of a zero line. They are used to display data of both positive and negative values. An example of a bilateral graph is shown below:

This bilateral graph is a depiction of fertility changes in Chile over the past 25 years. You can see from the graph that for most of the past 25 years there has been a decrease in fertility among Chileans, with the exception of a short period of increase in the late 80's early 90's.
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