From the press release:
The nation’s state-administered defined benefit retirement systems totaled $2.5 trillion in cash and investment holdings in 2011, a 14.6 percent increase from $2.2 trillion in 2010, according to new statistics from the U.S. Census Bureau. Earnings on investments were $410.6 billion, up from $291.1 billion in 2010. These statistics come from the 2011 Annual Survey of Public Pensions: State-Administered Defined Benefit Data, which provides an annual look at the financial activity and membership information for the nation’s 222 state-administered public-employee retirement systems, including revenues, expenditures, investment holdings, membership and beneficiaries. Statistics are shown for the nation and individual states. This information includes actuarial liability statistics, which project the total obligation required to cover costs for providing pensions to former and present employees.
Source: Erika Becker-Medina, U.S. Census Bureau, G11-ASPP-ST, August 2012