The Canada Pension Plan Investment Board, the nation’s biggest public pension plan, said it delivered gross investment returns of 1.9 percent in the latest quarter, with the strong Canadian dollar hurting its performance.

The CPPIB, which manages Canada’s national pension fund and invests on behalf of 20 million Canadians, said it ended the first quarter on June 30 with net assets of C$326.5 billion ($257 billion), up from C$316.7 billion on March 31.

The fund has diversified internationally, becoming one of the world’s biggest investors in infrastructure and real estate. It is also a major global investor in equities and bonds, and derives the majority of its earnings from overseas.

The strength of the Canadian dollar, which hit a two-year high in July, means that overseas earnings are not worth as much when they are converted back to the fund’s domestic currency.

“The strengthening Canadian dollar against most major currencies applied downward pressure, a trend that accelerated in the first half of the current quarter,” said Chief Executive Mark Machin.