The analysis by market research firm eMarketer projected that e-commerce sales would increase at a rate of 23.7 percent this year and would continue "double-digit growth" to exceed $4tr within five years.
In addition, analysts said that e-commerce's share of overall global retail sales would climb from 8.7 percent to 14.6 percent over that span.
"While the pace of growth for overall retail sales is subdued, the digital portion of sales continues to expand rapidly," researchers wrote.
The Asia-Pacific region should remain the world's largest e-commerce market throughout the forecast period. Those nations are expected to see a 31.5 percent sales increase this year as internet access, growing e-commerce competition and improved logistics continue to accompany a rising middle class.
North America will be the world's second-largest market at $423bn this year and should also see "consistent double-digit growth" as consumers broaden their online shopping habits to include groceries and other new categories.
The findings followed a report from Forrester’s last year that predicted U.S. B2B e-commerce would reach $1.13tr by 2020.
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