Mutation necessary

The data you subsetted with select() and filter() in the previous exercise is available for you here as subsetted_imf. Recall that mutate() is used to create new columns in a tibble/data frame and that group_by() can be used with summarize() to calculate statistics for one variable across the levels of another variable.

Note that the usd_conversion_rate variable corresponds to how much of the nation's currency is needed to equal one US dollar (USD).