Considering the audience and communication objectives of the data, how effective is this chart?

Title: Analyze a Line Chart

When Google faced antitrust allegations from the European Union, the company responded with a blog post and several line charts.

Read more about the situation at bit.ly/1yHwDXJ (https://www.bizcominthenews.com/bizcom_in_the_news/2015/04/google-responds-to-anti-trust-suit.html) and analyze the Travel sites in Germany chart included.

Which principles from this chapter does the author miss? Considering the audience and communication objectives of the data, how effective is this chart?