Stock market gains helped offset a drop in bond yields at the typical large U.S. defined benefit pension plan in July.

The “funded ratio” at a typical plan rose to 67.6% at the end of the month, from 66.6% at the end of June, according to consultants in the Stamford, Conn., office of Towers Perrin Forster & Crosby Inc.

Towers Perrin bases pension status figures partly on the performance of a hypothetical benchmark pension plan and partly on the actual pension results reported by 300 large U.S. companies.

The funded ratio has dropped 23% over the past 12 months, Towers Perrin reports.

A benchmark investment portfolio that Towers Perrin uses in analyzing plan performance experienced a 5.4% return in July. Projected liabilities increased 4.3%.