Raytheon Co., Waltham, Mass., expects to contribute $320 million to its worldwide pension plans this year and an additional $315 million in 2005, the company said in its 10-K filing. Raytheon expects $700 million in pension expenses in 2004 and $750 million in 2005, the filing said. The firm had $315 million in pension expenses for the year ended Oct. 31; the company changed its plan measurement date to Dec. 31 as of this year, a move that is expected to produce an after-tax gain of $34 million for pension benefits, the filing said. The plans' asset allocation last year was 67% equity, 26% fixed income, 4% other investments and 3% real estate. Raytheon had worldwide plan assets of almost $10 billion as of Oct. 31, and worldwide plan liabilities of $13.5 billion.