According to YP consultancy Simba:
Internet yellow pages spending is projected to increase 17.4% to $1.83 billion in 2009, accounting for 11.1% of total yellow pages market revenue . . .
By comparison, in the UK, Internet represents 20% of overall revenue for Yell (it was 12% of revenues for subsidiary Yellowbook in 2008 at YE).
Overall Simba said that IYP revenues in the aggregate (for the US market) are $1.83 billion for 2009.