HELSINKI (AP) — Norway’s sovereign wealth fund, the world’s largest of its kind, has hit a milestone value of $1 trillion, beating all expectations since its creation over 20 years ago.

Fund manager Norges Bank Investment Management said the value was recorded early Tuesday. It said the fund has been boosted by a rise in stock markets and a weaker U.S. dollar, which increases the dollar value of its holdings in other currencies.

Norway first deposited oil and gas profits into the fund in 1996 and CEO Yngve Slyngstad said nobody expected it to hit the trillion dollar mark at the time, calling the growth “stunning”.

The fund invests oil and gas proceeds mainly into stocks but also bonds and property worldwide to secure wealth for the Nordic nation’s 5.3 million people.