Web measurement company comScore Networks Inc. said its review of consumer e-commerce for 2001 shows that sales at domestic online retailers (excluding auctions) surged to an estimated $53 billion for the year.

The Reston, Va.-based company, which says it derives its estimates from tracking the actual buying activity of a representative cross-section of more than 1.5 million Internet users, said that excluding spending at online travel sites, sales totaled $33.7 billion, up about 20 percent from 2000.

Signs of mid-year softness in non-travel sales were offset by what was -- at the time -- a strong period of growth in the online travel sector, comScore said.

Following the events of Sept. 11 and as the holidays approached, the travel sector entered a slump from which it has not yet recovered, but at the same time, the Internet "became a channel of choice for consumers," the company said.

Non-travel spending in 2001 by quarter was an estimated $7.7 billion in the first quarter; $12.5 billion in the second quarter; $13.3 billion in the third; and $15.8 billion in the fourth.

Travel spending showed steady gains up until the fourth quarter. Travel spending per quarter was $3.7 billion in the first quarter, $4.9 billion in the second, $5.7 billion in the third and $5.0 billion in the fourth.

"In July and August, online travel sales reached a fever pitch, fueled by consumer comfort with buying online, deep price discounts, and new choices in online agencies," said Dan Hess, comScore vice president. "But after Sept. 11th, the sector's sales fell dramatically, before beginning a slow recovery. However, comScore data for the first two weeks of January 2002 show a strong resurgence in online travel spending."

The highest sales day of the year was Wednesday, Dec. 12 -- the height of the holiday season -- which posted $321.6 million for the day. The lowest sales day of the year was Jan. 1.

The average weekend day brings $97 million in sales, but average weekday (Monday-Friday) is a full 60 percent greater at $155 million, due to increased shopping from people at work.

Computer Hardware and Consumer Electronics were the hot products of the holidays; together these categories started the year at 19 percent of total sales and ended 2001 accounting for 24 percent.