After much wrangling (and following what looked like the death of the measure), Congress passed and the President signed an extension of the pension smoothing provisions that were in the 2012 legislation known by the acronym "MAP-21." The legislation passed this time because it is revenue generating (smoothing cuts required contributions, which increases taxable income and, therefore, taxes). The revenue helped balance expenditures included in the Highway and Transportation Funding Act of 2014.
In English, the provision "smooths" funding by holding off the impact of recent years' low interest rates. (I'll keep the math simple--there is a paragraph in Section 430 of the Internal Revenue Code that was scheduled to phase in lower rates over a period of years and the recent legislation just extended the period of years over which applicable rates will be held at a higher level. Higher rates reduces plan liabilities and, therefore, required funding.)
In English, the provision "smooths" funding by holding off the impact of recent years' low interest rates. (I'll keep the math simple--there is a paragraph in Section 430 of the Internal Revenue Code that was scheduled to phase in lower rates over a period of years and the recent legislation just extended the period of years over which applicable rates will be held at a higher level. Higher rates reduces plan liabilities and, therefore, required funding.)