The graph below shows the US consumers average annual expenditures on cell phone and residential phone services

Given is a line graph which delineates comparative data regarding the yearly spendings on cell phone and residental phone services in United States, in 10 years, from 2001 to 2010.
A glance at a graph reveals that the popularity of given services was exposed to different trends and while the figure for cell phone experienced a considerable growth, it saw a significant downward tendency. However, for all the time covered in the figure residental phone services was the most desired one, at the end spendings on cell phone was almost 2 times more than residental.
In the 2001, the difference was remarkable for 2 services with 200$ for mobile phone and a bit below 700$ for residental phone services. 5 years later, 2 figures met in the same point which is approximately 500$ average annual expenditures. Nonetheless, in 2010 the gap was significant again, with approximately 750$ for cell phone and 400$ for residental services.