Google has made a change to how the rating extensions for AdWords ads work. Google says the change will keep them fresher and more relevant.

“Previously, we would show seller rating extensions only for advertisers that have at least 30 lifetime reviews and a 4-star average,” explains AdWords product manager Liza Ma. “Moving forward, we will only show seller rating extensions for advertisers that have at least 30 reviews over the last 12 months and a 4-star average.”

“Since customer opinions about a business can evolve over time, this change will help make seller rating extensions more useful and relevant for searchers,” adds Ma. “It should also benefit businesses that satisfy customers and garner positive reviews on an ongoing basis.”

According to Google, the extensions often lead to higher clickthrough rates.

Last week, Google announced some new local targeting options in 11 countries.