The "internet economy" grew 68 per cent between the first quarters of 1998 and 1999, and now accounts for 2.3 million jobs, according to a study.
The study, conducted by the University of Texas Center for Research in Electronic Commerce and commissioned by Cisco, predicts the Net economy will grow to $US7 billion for all of 1999.
In June, the center estimated that the internet generated $301.4 billion in revenue last year.
E-commerce was particularly strong, with online sales soaring 127 per cent to $37.5 billion in the first quarter of this year. The number of jobs generated by online sales jumped 78%, to more than 900,000, the study concluded.
What the study called "internet infrastructure" also showed a healthy increase, growing 50 per cent to $40.1 billion in the beginning of this year. The application sector rose 61 per cent to $22.5 billion, and "intermediaries" increased 52 per cent to $16.7 billion.
The study defines the internet economy as worldwide revenue generated by US-based companies.