eMarketer reports OneUpWeb updated a search study that shows that longer keyword phrases continue to convert at higher rates, up to a point. Keyword phrase conversion rates increase from about six percent with a one-word phrase to 38 percent with a four-word phrase, quite possibly due to the tendency of four-word phrases to generate much more relevant results. But after four words, conversion rates drop quite quickly. Phrases with six or more words convert only at about a nine percent rate. Over the last three months of 2004, these rates remained fairly consistent.