Rising prices were cited as one factor working against spending, but "it's clear that the increase in the country's unemployment rate along with the shock of the financial market meltdown have had a negative impact on the psyche of the American consumer, and the effects were clearly felt in the online retail sector," said ComScore's chairman, Gian Fulgoni, in a written statement. "October represented the softest single month of online retail growth on record, and we can only hope that the recent sharp drop in oil prices will cause a continued easing of inflation and a strengthening in consumer spending as we enter the critical holiday shopping season."

The news comes barely a week before black Friday, the day after Thanksgiving, when retailers traditionally turn their first profits of the year, and "Cyber Monday," which in recent years has become a banner day for e-retailers as shoppers return to work and use their offices' broadband connections to do holiday shopping online.

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