summary of material modifications

This is a summary of recent amendments and other important changes in the Western Conference of Teamsters Supplemental Benefit Plan (the “Plan”) and the related Western Conference of Teamsters Supplemental Trust Fund (the “Fund") occurring since the April 1, 2003 to March 31, 2004 Plan Year. You should retain this Summary with your copy of the last Summary Plan Description (“SPD”) booklet (dated April1, 2003). Please refer to the SPD booklet to help you understand the changes described below and to refer to the capitalized terms.

First, effective October13, 2005, the Trustees expanded the Plan’s definition of “Pensioner” to include persons who retired from a non-Contributing Employer but who later returned to work for a Contributing Employer for at least two years and who, upon their subsequent retirement, qualify for a “recomputed benefit” under the terms of the Western Conference of Teamsters Pension Plan (the “Primary Plan”), even if they previously had elected an earlier retirement date under the Primary Plan. If you believe you may qualify for a benefit based upon your return to employment for at least two years prior to your retirement from a Contributing Employer, you should apply (or reapply) for a Supplemental Plan benefit.

Second, normally a Pensioner must retire from a Contributing Employer in order to qualify for a Supplemental Plan benefit. However, effective for persons first eligible on or after April1, 2004, the Trustees have expanded, from 24 months to 36 months, the period preceding your retirement during which you can earn a single benefit accrual under the Plan if you worked for a Contributing Employer for at least 1,000 hours during that 36-month period (even though you retire from a non-Contributing Employer).

Third, effective for the 2006/2007 Plan Year, the Trustees increased the minimum Basic Benefit payable to Pensioners or Surviving Spouses who are limited only to one benefit accrual to $150 (or its reduced actuarial equivalent for married Pensioners).

Fourth, also effective for the 2006/2007 Plan Year, the Trustees declared a one-time, non-annuity, non-recurring lump sum benefit in the amount of $160, payable to all Pensioners and Surviving Spouses receiving a benefit as of March31, 2007, but excluding anyone whose minimum annual benefit was increased to $150, as described above. It is anticipated that this benefit will be paid in mid to late 2007.

Fifth, the Trustees delayed until 2008/2009 the effective date of a Plan amendment reducing the amount of annual accruals for a limited number of Pensioners whose last Contributing Employer contributesto the Plan at a reduced rate.

None of the above-described benefit improvements are payable prior to each amendment’s respective effective date. Eligibility for a benefit is governed by the language of the Plan itself, not by this Summary. If you believe you are affected by any of the above amendments or if you need another copy of the SPD booklet, contact Southwest Administrators at (877) 350-4792 (ext. 657)(toll free) for more information.

In the section of the SPD entitled “Additional Information About the Plan”, please note the following:

Under “Union Trustees”, KenLundgren, Teamster Local No. 542, 4666 Mission Gorge Place, San Diego, California92120 has replaced RandyCammack as a Trustee.

Under “Employer Trustees”, MichaelMcMillan, Vice President Labor, Yellow Transportation, 10990 Roe Avenue, Overland Park, Kansas66211 has replaced BenThroop as a Trustee, and JimRoberts has replaced BenThroop as the Board Secretary.

Under “Investment Manager”, the address for Dodge & Cox has changed to 555 California Street, 40th Floor, San Francisco, California94104.

Under “Where To Serve Legal Process”, the person at Southwest Administrators to whose attention any service of legal process should be directed has changed from Michael Uranga to Christopher Espinoza.

February, 2007

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