2. if public plans were required to go one step further and fully incorporate expected future mortality improvements.

The brief's key findings include:

• Using the private-sector standard, public plans underestimate life expectancy by only 0.5 years, reducing the 2013 funded status of state and local plans from 73 percent to 72 percent.
  
  
• Incorporating future mortality improvements would increase life expectancy by 2.3 years and reduce the funded ratio of public plans from 73 percent to 67 percent.

Plans’ liabilities are affected, of course, by the longevity of their members, and the brief explores the degree to which liabilities are affected, calculating that “state and local pension plans would see their liabilities increase by 3.5 percent for each additional year of life expectancy.”

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When the differences among longevity tables are factored in, it becomes clear that some plans, because of the way they calculate life expectancy, will be more greatly affected by a change from one table to another, while other plans will not see such drastic effects.

The public sector, the brief said, is going to great efforts to make sure its life expectancy assumptions are up to date. Reassuringly, the brief said, “The question underlying this analysis is whether outdated mortality assumptions are a serious problem among state and local plans. The answer appears to be ‘no.’”