Exercise

# Visualizing median GDP per capita over time

A line plot is useful for visualizing trends over time. In this exercise, you'll examine how the median GDP per capita has changed over time.

Instructions

**100 XP**

- Use
`group_by()`

and`summarize()`

to find the median GDP per capita**within each year**, calling the output column`medianGdpPercap`

. Use the assignment operator`<-`

to save it to a dataset called`by_year`

. - Use the
`by_year`

dataset to create a line plot showing the change in median GDP per capita over time.**Be sure**to use`expand_limits(y = 0)`

to include 0 on the y-axis.