Excerpt: Just before the bell, the IRS issued much-needed relief for pension plans in calculating their minimum required contributions. Released on March 31, the deadline by which many calendar year plans were required to have an actuary's certification of the plan's funded percentage, the relief provides greater flexibility for plans that use the corporate bond yield curve in determining benefit liabilities. The IRS announced that, until final regulations are issued, it will not challenge the use of a monthly yield curve for any applicable month (i.e., the month containing the valuation date and the four preceding months).