A swiss sum

Can you use the given image to say something about the sum of an infinite series?

Problem

The Basel problem, dating back to the 17th century, asks for the sum of the infinite series

$$\frac{1}{1^2} + \frac{1}{2^2} + \frac{1}{3^2} + \frac{1}{4^2} + \frac{1}{5^2} + \cdots$$

What does this image tell you about the sum?

 

Image
A Swiss sum