How much would you pay for more Facebook "likes"? If you're the State Department, you'd shell out about $630,000.

According to a May report from the State Department's Inspector General, which was recently made public, the agency spent more than half a million dollars on two campaigns in 2011 and 2012, intended to boost the number of fans for its English-language Facebook pages.

The effort actually worked - both pages jumped from 100,000 fans to about 2 million. But while the four pages for the State Department's Bureau of International Information Programs (IIP) had about 2.5 million fans each as of March 2013, engagement leaves something to be desired, prompting questions about whether that $630,000 was a good use of agency funds.

As of mid-March, only about 2 percent of fans had liked, shared, or commented on anything posted to the pages. Most of the engagement was in the form of "likes"; most posts had fewer than 100 comments or shares, the IG found.

Meanwhile, a Sept. 2012 update to the way that content displays on users' newsfeeds means that many of the State Department's updates are not being seen by most of their Facebook followers. "If a user does not interact with a site's postings, after a time these postings will no longer appear in the user's newsfeed unless the site buys sponsored story ads to ensure their appearance," the IG concluded.

A Facebook post on "Women in the Web" posted by State, for example, reached 360,000 people with advertising, but would only have been seen by 27,000 without it.

As a result, the focus of late has been on sponsored stories rather than increasing the number of fans. "However, engagement is a means, not an end," the IG warned. "The bureau could reduce spending and increase strategic impact by focusing its advertising not on raising overall fan numbers or general engagement statistics but on accomplishing specific PD [public diplomacy] goals."

The IG argued that the State Department's media team should be pickier about what they choose to promote and to whom. Making sure things are strategically planned and well-targeted would be a better use of resources than simply sending out updates to millions of people and seeing what sticks. The IIP is now developing a social media policy strategy to clarify goals and priorities in order to make that a reality, the IG said.