By 2015, e-retail sales will hit $278.9 billion in the U.S., Forrester says.

Online retail sales will grow at a 10% average annual growth rate from 2010 to 2015 in both the United States and Europe, though the rate will steadily decline through 2015, Forrester Research Inc. says. The figures do not include online travel and motor vehicles sales.

In its recently released ForecastView reports, Forrester projects that online retail sales in the U.S. will increase 11.98% this year compared with 2010, to $197.3 billion from $176.2 billion. The annual rate of increase will decline slightly each of the next several years, with online retail sales in 2015 rising 7.81% over 2014, to $278.9 billion from $258.7 billion, Forrester projects. That represents a 9.62% compound annual growth rate for the U.S. over the five-year forecast period.

In Western Europe, Forrester projects online retail sales will rise 13.10% this year over 2010, to €91.90 billion ($125.57 billion) from €81.25 billion ($111.02 billion). As in the United States, Forrester projects the annual rate of increase will decline slightly in each of the next several years, with online retail sales in 2015 rising 7.84% over 2014, to 133.64 billion euros (US$182.53 billion) from 123.92 billion euros (US$169.31 billion). The projected compound annual growth rate for Europe over 2010-2015 is 12.47%.

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