Today in 2005, Shop.org announced in a press release “‘Cyber Monday’ Quickly Becoming One of the Biggest Online Shopping Days of the Year.” According to Shop.org/BizRate Research 2005 eHoliday Mood Study, 77% of online retailers said that their sales “increased substantially” the previous year on the Monday after Thanksgiving.

The release explained the phenomenon: “Experts believe that an increase in web traffic could stem from the fact that consumers may have faster or more secure Internet connections at work and choose to shop there, or that they were unable to finish all of their shopping over the Thanksgiving weekend. Analysts also expect many consumers to shop on Cyber Monday from home after work or when their children are sleeping. Regardless of the reason or the time of day, consumers are expected to head online in droves on Cyber Monday, many during work hours.”

Cyber Monday 2012 was about 30% larger than it was the prior year.

Update: According to Custora Pulse, Cyber Monday 2013 was the biggest online shopping day in history, with 18.2% increase in online sales compared to Cyber Monday 2012. My summary here