Yet after another very challenging year for integrated oil producers, there are still a few things I like about Exxon - so, is it time to buy its shares at $77.9? Incidentally, if you are not familiar with oil trades, and you want to get a feeling for what kind of risk you'd be taking by betting on integrated oil manufacturers with oil prices trading below $40 a barrel, then I suggest you give a close look to the chart below. China is currently a drag on expectations for the world's economy, and this is arguably the biggest difference between now and the post-2008 world.