Online marketing expenditure in the US will continue to grow over the next five years, reaching $61.3bn (£30bn) in 2012, according to predictions from Forrester Research.

Online advertising will be worth $18.4bn (£9bn) this year, accounting for 8% of total advertising expenditure. Forrester predicts that online ad expenditure will grow by 27% annually over the next five years, and that online marketing will account for 18% of total ad spend in 2012.

Search will account for most ad expenditure, according to the study. Spending on search marketing will reach around $8.1bn (£3.9bn) this year, with $6.1bn (£2.9bn) to be spent on online display ads, and $2.7bn (£1.3bn) on email marketing.

Spending on search engine marketing is predicted to triple over the next five years, growing by 26% annually, and reaching a total of $25bn (£12bn) by 2012.

Paid search is predicted to account for the majority of that spending, growing from $4.5bn (£2.2bn) to $10.1bn (£4.8bn) over the next five years.

SEO, meanwhile, is predicted to be worth $8.9bn (£4.3bn) by 2012, compared with $1.9bn this year.
The two industries that account for the most online marketing spend are the travel and hospitality industry, which spent $8.7bn this year, while next was the retail industry, which accounted for $6.2bn in online ad spend this year.

As well as search, spending on online display advertising and email marketing is also predicted to grow, though Forrester expects that email marketing will be overtaken by online video advertising by 2012.