Search term prices rose 3 percent in June, reaching an average of $1.72, up from $1.67 in May, according to the Fathom Online Keyword Price Index, reports MediaPost. Since September, when the index was first published, prices have increased some 25 percent.

Keywords related to wireless services increased 19 percent in June, reaching $1.19, the highest for the category since the index started. Retail keywords were up 9 percent, to $0.53; in November, their average was $0.60.

Keyword prices in other categories registered small increases (investing, up 5 percent; consumer service, 3 percent; mortgages, 3 percent; cars, 2 percent; and travel, 1 percent). Broadband-related search-term prices fell 2 percent, to $1.97.

Fathom indices are based on a weighted average of bid prices of the top-five ranked positions across U.S. Tier 1, 2, and 3 search vendors of keywords, not including brand keywords. The keyword list for each industry consists of the 500 most-queried keywords.