The website Statista provides statistics and charts on business, industry, etc. Now you can easily cite them in your assignments. For example:
On the right of this chart’s Statista page you can see the Citation option:
Choose Harvard and you get this reference:
Facebook. (2019). Number of monthly active Facebook users worldwide as of 1st quarter 2019 (in millions). Statista. Statista Inc.. Accessed: July 17, 2019. https://www.statista.com/statistics/264810/number-of-monthly-active-facebook-users-worldwide/
You can copy this reference and paste it into your assignment.