Fed by high food costs, consumer prices in August rose 1.79 percent, adding to Costa Rica's steady inflationary rate that during the past year has surpassed 15 percent.

Groceries and nonalcoholic beverages led the upward charge, rising 2.42 percent in August and 26.6 percent since last September, according to National Statistics and Census Institute (INEC).

Transportation costs rose 3.19 percent in August, bringing their 12-month increase to just over 19 percent, while entertainment and cultural events rose 2 percent last month.

The 15.4 percent increase in consumer prices between September 2007 and August was the largest for that period in more than 10 years.

Between September 2006 and August 2007, consumer prices rose 8.56 percent, according to INEC.