SAN FRANCISCO (CBS/AP) — A grand jury said San Francisco’s pension fund investments were too risky.

The civil grand jury said the San Francisco Employees’ Retirement System has used a high-risk investment policy for the past 28 years and losses are costing taxpayers too much money.

The pension fund draws upon employee contributions, taxpayer dollars and returns on investments.

The pension fund dropped from $17.4 billion in 2007 to a low of $11.1 billion in 2009.

The city contributed about $433 million from its $6.6 billion budget last year to ensure retirement benefits for 26,000 workers.

The grand jury said the city’s tab was expected to increase and San Francisco taxpayers cannot afford to make up for the shortfall.

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