Brand Managers Ignore 80 Percent of Complaints on TwitterU.S. companies are under the global average for responding to consumers' questions and concerns on social media, a new report says.

Twitter can be a very effective tool for addressing questions about a brand's product or services, but it's not being used effectively, according toa new study.

Socialbakers reports that 80 percent of questions posed to United States companies are ignored. That's a 20 percent higher rate than on Facebook, where brand managers are more likely to answer customers' questions.

Socialbakers arrived at the number after studying 6.5 million tweets and 1.4 million Facebook posts across 50,000 brands. They used the data to break down response rates by country.

Egypt had the highest response rate on Twitter at 70 percent, while the U.S. lagged toward the bottom at just 18 percent. The U.S. also came in at the bottom for its response rate on Facebook, with 59 percent. The average response rate was 74 percent, with Denmark, Pakistan and Norway tied for the highest response rate of 93 percent.

This could start to become a real problem for brands. ASimply Measured studyshows that mentions of customer service handles are up 41 percent this year, andMashablereported that Comcast received almost 9,000 social media mentions within one week.

If mentions are up and response rates are low, will customers get the picture that brands don't want to answer their question on social platforms, or will this start to snowball into a bigger problem for brands?