Notice how the data appears to repeat depending on the month.
See solution.
Practice makes perfect
Attendance at a National Park will probably exhibit a periodic behavior because people are more likely to go to the parks during their vacation months. Let's take a look at the following histogram.
This is data taken from the Yellowstone National Park visitor statistics page for attendance between 2017 and 2019. We can see how this graph resembles a sine curve.
The attendance increases over the year until a maximum is reached in July. Then it starts to decrease until a minimum is reached. This pattern repeats as we move to the following years.
We can also notice how the attendance appears to be consistent depending on the month. This means that every year we can expect approximately the same attendance each month.
The time it takes to get from a maximum to a maximum (or a minimum to a minimum) is called the period of the function. We say that the function that represents the attendance at the park has a period of 1 year.
