BP didn't think it important to include [the 2010 Deepwater Horizon spill] in the report because, according to the fine print, there's been "no accurate determination" of how much oil actually leaked into the Gulf of Mexico. And so because there's no exact measure, they didn't think they should include it.
Just to be clear, coming up with a perfectly accurate measure of how much oil BP spilled in 2010 would be impossible. However, a team of scientists worked diligently to come up with an estimate, the massiveness of which blows away the above totals combined: 205 million gallons, or about 776 million liters.
Chart Of The Day II