When you publish a story on Wattpad you will see a button/option under continue writing that says 'Stats'. Now if you are wondering what 'Stats' is its the statistics of your story such as the number of unique readers and votes. 

When you first click on Stats you will be on an overview page that will have charts like this with the number up the side and dates along the bottom:

In 'Engagement' you will find a chart which shows you a graph of completed reads by part, votes by part, and comments by part

It also includes the demographics for your story which lets you know what percentage of your readers fall inside a certain age group, gender, or country. 

Demographics:

When you go into demographics the first thing you will notice is the pie charts that look like this:

When you hover over a coloured section, as I did with purple, it will show you what that group is and percentage. When you scroll down you will see a map like this:

In the top left corner there are the + and - icons to zoom in and out on the map. When you hover over any area on the map it will tell you the name of the country/land and the percentage. 

The higher the percentage the darker blue it is coloured.