How defined contribution plans and 401(k)s affect employer pension costs

We investigate the pension choices made by over 700 firms between 1981 and 1998 when DC plans expanded and overtook DB plans. Their average pension contribution per employee dropped in real terms from $2,140 in 1981 to $1,404 in 1998. At the same time, the share of their pension contributions attributed to defined contribution plans was 23% in 1981 and increased to 68% in 1998. By analyzing pension plan data from the IRS Form 5500 and finances of the plan's sponsoring employer from COMPUSTAT with a fixed-effects ordinary least squares model and a simultaneous model, we find that a 10% increase in the use of defined contribution plans (including 401(k) plans) reduces employer pension costs per worker by 1.7–3.5%. This suggests firms use DCs and 401(k)s to lower pension costs. Lower administrative expenses may also explain the popularity of DC plans. Although measuring a firm's pension cost per worker may be a crude way to judge a firm's commitment to pensions, this study suggests that firms that provide both a traditional defined benefit and a defined contribution plan are the most committed because they spend the most on pensions. Further research, especially case studies, is vital to understand employers' commitment to employment-based pension plans.