These 4 charts illustrate Russia's gas leverage over Europe

It's hard to overstate the power that Russia has over Europe. Each year, Europe pays Russia and its gas companies approximately $250 billion to supply 30% of Europe's energy needs. Some countries, like Armenia and Belarus, are 100% dependent on Russian gas.

To illustrate the point, Radio Free Europe/Radio Liberty has created a series of interactive chartsto show which countries rely on Russia the most and how much each one must pay for their gas. Click through to see just how dependent Europe is.