NEW YORK: Radio revenues in the US fell by 10% to $16.5 billion (€12.9bn; £11.3bn) in 2008, the medium's third consecutive annual decline, according to the Radio Advertising Bureau.

Radio is one of the medium's predicted to struggle during the US advertising downturn, with adspend set to slide by around 4% this year.

In 2008, off-air revenues, such as online activity and experiential marketing partnerships, increased by 7% to a total of almost $1.8 billion, and the RAB predicts this total will rise to $2bn this year.

National radio revenues were down by 12% to $2.9bn, with local revenues also falling by 10% to $13.6bn, while network radio remained largely flat at $1.2bn for the year as a whole.

In the fourth quarter, local advertising revenues fell 13% to $3.2bn, with national spending also down 14% to $735m, network falling by 4% to $298m, and off-air growing by just 1% to $444m.

In terms of categories, overall annual spending levels only rose in the professional services (+6%), insurance (+5%) and restaurant (+1%) sectors.

Data sourced from RAB/AdWeek; additional content by WARC staff