Most U.S. troops in mainland Japan and Okinawa saw a dip in their paycheck July 1 as the cost-of-living allowance dropped throughout the country.

In two weeks, COLA has fallen either four or two points, depending on location. But since May the decline has been steeper.

For an E-6 stationed at Naval Air Facility Atsugi near Tokyo with 10 years of experience and three dependents, his COLA for a two-week pay period was $528.33 on May 1. For the first two weeks in July, that technical sergeant is bringing home $422.67 in COLA — a difference of about $106.

An E-2 assigned to Okinawa living in the barracks is making about $12 less a month in July, if COLA rates hold steady. Compared to May, he or she is earning about $44 less a month in COLA.

According to the latest message posted Monday on the Per Diem, Travel and Transportation Committee’s Web site, COLA changes in Japan this month are due to a fluctuating foreign currency rate in relation to the U.S. dollar.

In adjusting COLA for the current pay period, the committee used a Japanese yen rate of 107.41, compared to 104.16 for the second half of June.

The former is nearly a 10-point drop since April in the yen-to-dollar exchange rate used by the committee to set COLA.

The lowest exchange rate used by the committee this year was a yen rate of 92.9, for the pay period beginning April 1.

That same technical sergeant at Atsugi earned $581.17 per pay period in COLA then.

According to a July 1 story in the Wall Street Journal, the dollar gained 6.5 percent on the Japanese yen from April to June.

For more information or to calculate COLA rates, go to http://perdiem.hqda.pentagon.mil/perdiem/ocform.html.