nbcuniversal media , llc our consolidated balance sheet also includes the assets and liabilities of certain legacy pension plans , as well as the assets and liabilities for pension plans of certain foreign subsidiaries . as of december 31 , 2015 and 2014 , the benefit obligations associated with these plans exceeded the fair value of the plan assets by $ 67 million and $ 51 million , respectively . other employee benefits deferred compensation plans we maintain unfunded , nonqualified deferred compensation plans for certain members of management ( each , a 201cparticipant 201d ) . the amount of compensation deferred by each participant is based on participant elections . participants in the plan designate one or more valuation funds , independently established funds or indices that are used to determine the amount of investment gain or loss in the participant 2019s account . additionally , certain of our employees participate in comcast 2019s unfunded , nonqualified deferred compensa- tion plan . the amount of compensation deferred by each participant is based on participant elections . participant accounts are credited with income primarily based on a fixed annual rate . in the case of both deferred compensation plans , participants are eligible to receive distributions from their account based on elected deferral periods that are consistent with the plans and applicable tax law . the table below presents the benefit obligation and interest expense for our deferred compensation plans. .
what was the percent of the interest expense of the benefit obligation in 2015
retirement investment plans we sponsor several 401 ( k ) defined contribution retirement plans that allow eligible employees to contribute a portion of their compensation through payroll deductions in accordance with specified plan guidelines . we make contributions to the plans that include matching a percentage of the employees 2019 contributions up to certain limits . in 2015 , 2014 and 2013 , expenses related to these plans totaled $ 174 million , $ 165 million and $ 152 million , respectively . multiemployer benefit plans we participate in various multiemployer benefit plans , including pension and postretirement benefit plans , that cover some of our employees and temporary employees who are represented by labor unions . we also partic- ipate in other multiemployer benefit plans that provide health and welfare and retirement savings benefits to active and retired participants . we make periodic contributions to these plans in accordance with the terms of applicable collective bargaining agreements and laws but do not sponsor or administer these plans . we do not participate in any multiemployer benefit plans for which we consider our contributions to be individually significant , and the largest plans in which we participate are funded at a level of 80% ( 80 % ) or greater . in 2015 , 2014 and 2013 , the total contributions we made to multiemployer pension plans were $ 77 million , $ 58 million and $ 59 million , respectively . in 2015 , 2014 and 2013 , the total contributions we made to multi- employer postretirement and other benefit plans were $ 119 million , $ 125 million and $ 98 million , respectively . if we cease to be obligated to make contributions or were to otherwise withdraw from participation in any of these plans , applicable law would require us to fund our allocable share of the unfunded vested benefits , which is known as a withdrawal liability . in addition , actions taken by other participating employers may lead to adverse changes in the financial condition of one of these plans , which could result in an increase in our withdrawal liability . comcast 2015 annual report on form 10-k 166 .