The annual BP Statistical Review of World Energy is an essential reference source. It gives production and consumption statistics for many countries and all the regions in the world, disaggregated by oil, gas, coal, nuclear energy and hydroelectricity.

As I write this, Brent crude is trading at about $130 per barrel. The price has doubled over the last year and quadrupled over the last three.

Five years have passed since US and UK forces invaded Iraq and overthrew Saddam Hussein. There would be few people who expected the problems there to have lasted so long, with little sign of solutions in the foreseeable future.