system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why are the gas prices dropping so rapidly after being to high for so long?
gpt
- The cost of producing oil mostly depends on its accessibility.

- OPEC is a group of oil producing countries who make up 45% of the world supply.

- OPEC countries like Saudi Arabia have huge relatively easy to access oil deposits, meaning they could produce lots of cheap oil whenever they want.

- Most of the cheap & easy to access oil fields in the US have largely been exhausted or are nearing some limit of production.

- The US has the largest Shale oil deposits on earth, but shale is a lot more expensive to extract so oil has to be above a certain price to make it cost effective to extract from shale.

- Over the last few years oil prices have risen high enough that extracting shale oil became economically viable.

- The viability of shale oil led to a oil boom in the US that was causing us to consume less OPEC oil and more of our own. 

- OPEC didn't want their market share eroded by US shale oil.

- So OPEC increased production effectively lowering their own prices and the price of oil in general.

- OPEC hopes to make oil cheap enough that it would make US shale production more expensive.

- As long as OPEC is exporting large amounts of relatively cheap oil, the companies in the US will have to work with lower margins or no profit at all which means less oil production in the US and more consumption of OPEC oil. 

- This wont last forever, eventually OPEC will lower their production and prices will go up again.