Rising interest rates and solid stock market returns are improving the health of large U.S. employers’ defined benefit pension plans.

Consultants at Watson Wyatt, Washington, give that assessment in a review of 2005 results at Fortune 1000 employers’ defined benefit plans.

Pension plan liabilities posted a high amount of financial risk for only 9% of the companies studied in 2005, down from 17% in 2003, the consultants report.

Meanwhile, 60% of pension operations appear to pose little risk to the sponsors’ core business, up from 51% in 2003, the consultants report.

The overall pension plan funding level increased to 92% in 2005, from 82% in 2002, the consultants estimate.