That’s because TNS, which provides the likes of us will sorts of useful data, doesn’t actually track all of the Internet and radio ad business. TNS tracks Internet display advertising, but not search. So, um, Google’s not in there. And in radio, TNS doesn’t measure spending at the two biggies: CBS Radio and Clear Channel.
TNS puts the U.S. radio market at $10.7 billion in 2007, but most other estimates put it at about twice that. Similarly, TNS put online display advertising at $11.3 billion, about half of the total Internet advertising market.
Grouchy nitpicking aside, TNS’ conclusion is still likely accurate. The Internet Advertising Bureau put 2007 Internet spending at $21 billion, a 24% increase. The Radio Advertising Bureau estimated the radio ad market at $19.6 billion, a 2.5% decrease.