Several years after from the financial crisis of 2008, state pension funds continue to languish. According to data released this week by Milliman, Inc. and by the Pew Center on the States, there was a $859 billion gap between the obligations of the country’s 100 largest public pension plans and the funding of these pensions. Most of these are state funds, and state legislatures have attempted to respond to this growing crisis by making numerous reforms to try to combat this growing deficit.

Read: Nine States with Sinking Pensions

In 2010, only Wisconsin’s pension funds were fully funded. Nine states, meanwhile, were 60% funded or less — this would mean that at least 40% of the amount the state owes current and future retirees is not in the state’s coffers. In Illinois, just 45% of the state’s pension liabilities were funded. In some of these states, the gap between the outstanding liability and the amount funded was in the tens of billions of dollars. California alone had $113 billion in unfunded liability. Based on Pew’s report, “The Widening Gap Update,” 24/7 Wall St. identified the nine states with sinking pensions.

Each year, actuaries determine how much a state should contribute to its pensions to keep them funded. Many states, for various reasons, did not pay the full recommended contributions for 2010, while others have been paying the recommended amount for years. In an interview with 24/7 Wall St., Milliman Inc. principal and consulting actuary Becky Sielman explained that despite states making the recommended payments, many large individual public retirement funds are still underfunded.

Of the nine states with pensions that are underfunded by 40% or more, three paid more than 90% of the recommended contributions, and two, Rhode Island and New Hampshire, paid the full amount. Despite this, pension contributions were still generally higher in states that were better funded. Of the 16 states that were at least 80% funded — a level experts consider to be fiscally responsible — 11 contributed at least 97% of the recommended amount.

In an interview with 24/7 Wall St., Pew Center on the States senior researcher David Draine explained why, despite paying the full amount, several states continued to be severely underfunded. He pointed out that meeting contributions was important. He added that states that made full contributions in 2010 were 84% funded on average, compared to those that did not, which were only 72% funded.

To explain why several states that are making full contributions are still underfunded, Draine said much of it has to do with investment losses. “The 2000s have been a terrible period for pension investments that have fallen short of their expectations … that’s a big part of the growth in the funding gap.”

Unfunded liability can also grow due to overly optimistic assumptions about investment growth, pension payments that become deferred, and an increase in benefits or an increase in the number of beneficiaries without a corresponding increase in contributions, Draine explained.

Based on the Pew Center for the States report, “The Widening Gap Update,” 24/7 Wall St. identified the nine states with public pensions that were 60% or less funded as of 2010. From the report, we considered the total outstanding liability, the total amount funded, and the proportion of the recommended contribution each state made in 2010. We also reviewed the level of funding for the 100 largest pension funds in each state, provided by Milliman’s Public Pension Fund Study, which covered a period from June 30, 2009, to January 1, 2011.