BlackRock Chief Executive Officer Laurence D. Fink, who last year said he would invest 100% of his personal wealth in equities, said pension funds won’t meet their liabilities unless they put more money in stocks.

“I do believe most plans that I know have underinvested in equities,” Fink said today at the National Association of State Treasurers Issues Conference in New York. In a low interest rate environment, increasing stock holdings is the only way for pension funds to meet their obligations, he said.

The Standard & Poor’s 500 Index has surged 26 percent this year, challenging 2003 for the biggest annual gain in the last 15 years, as the Federal Reserve refrained from reducing its monthly bond purchases. Central-bank policy makers have been scrutinizing data to determine whether the economy is robust enough to withstand a reduction in their support.

Pension funds have to focus on the longer-term view and can’t look at quarterly or yearly returns when allocating money to assets, Fink said. Since March 9, 2009, when the stock market closed at its lowest after the financial crisis, the S&P 500 has advanced 165 percent.

“I truly believe the experience we’ve just witnessed over the last several years explains more than ever why you have to have an outcome-oriented investment process,” Fink said, referring to the stock market rally.