Ecommerce sales are forecast to increase 17% to $1.2 trillion worldwide this year, led by growth in the Asia-Pacific region.

Indonesia is expected to experience greater ecommerce growth, proportionately speaking, than any other country this year, according to estimates published Thursday by eMarketer. Online sales are expected to increase 71.3% to $1.8 billion. China, whose ecommerce market is already more than 100 times larger than Indonesia's, is expected to grow the second fastest, increasing 65.1% to $181 billion. (Other groups believe China is generating much more than that already.)

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Collectively, the Asia-Pacific region is expected to generate $388.8 billion in online sales in 2013, up nearly a quarter from 2012. The only region that is growing faster is the Middle East and Africa, currently the world's smallest ecommerce market. Sales in that region are estimated to grow by nearly a third to $27 billion this year.

North America is still the world's largest ecommerce driver, estimated to pull in $419.5 billion this year. As the most mature market, its growth rate is also the slowest, expected to increase 12.5% this year, about 4.5% below the global average. Western Europe is also seeing slowing growth: Online sales there this year are forecast to increase 14% to $291.5 billion, dropping into the single digits of growth beginning in 2015.

By 2014, the Asia-Pacific region is expected to become the largest ecommerce market in the world.

Image courtesy of Intel Free Press and eMarketer