The Aramco investment plan, by the numbers

The world's largest oil company will soon become the world's largest public investment fund.

That's big news, but what exactly does it mean?

Saudi Prince Mohammed bin Salman said earlier this month that his country would transfer ownership of the Arabian American Oil Company and some other national assets to the Public Investment Fund, one of several sovereign wealth funds through which the country invests excess cash from its oil and gas operations.

Initially, only about 5 percent of Aramco will be listed on the Saudi stock market. But if investors are willing to pay $10 for each barrel of reserves left in the country, Aramco as a whole should be worth about $2.7 trillion.

Simply by transferring Aramco equity to the PIF, the fund will become the biggest on Earth. Here's how the newly endowed fund would stack up compared with the other sovereign wealth funds, as tracked by the Sovereign Wealth Fund Institute.

Before being chosen to receive trillions in assets, the PIF was worth only about $5 billion and mostly held stakes in Saudi companies. It recently started looking outside the kingdom for purchases, including a 38 percent stake in a South Korean engineering firm for $1.1 billion in July and a long-term deal with Russia the same month.

The transfer of the country's oil company is only the start of a diversification plan to help Saudi Arabia move away from dependence on oil revenues. The fund said it plans to have 50 percent of its holdings in foreign investments by 2020.

That suggests that the new fund will be making some big purchases abroad, and it will have some serious clout in those transactions. Here's how the proposed PIF will stack up compared to the more than 14,000 global mutual funds tracked by FactSet.

FactSet tracks about 41,000 mutual funds across the globe with positive assets under management. Based on the latest figures available, those funds control about $27 trillion in assets. So the new fund would have the buying power of about 10 percent of the total current global mutual fund market.

Other measures of the total assets under management for paid fees (a different metric from a different database that includes other types of funds) give a total of around $74 trillion. Even by that measure, the new fund would be worth about than 3 percent of the world's total invested assets.

That's a solid chunk of assets that will change the playing field for investors across the globe. The Aramco initial public offering is expected to take place in 2017.