NEW YORK (AP) — This year more Americans than ever are expected to make their lists, check them twice, and then click the “add to cart” button.

Forrester Research said Monday that it expects U.S. consumers to spend $89 billion online in November and December. That’s up 13 percent, or about $10 billion, from a year ago.

Analyst Sucharita Mulpuru said she thinks online shopping will make up 14 percent of total retail spending over that period. She estimated that 3.4 million Americans will try holiday shopping online for the first time this year.

Forrester’s figures exclude spending on items such as gasoline, travel, restaurants and autos, except for replacement parts.

Mulpuru said her estimate would be higher if Thanksgiving were occurring earlier. The holiday always falls between Nov. 22 and 28, and it will be on Nov. 27 this year. That means the busy holiday shopping period between Thanksgiving and Christmas is shorter than in most years. In 2013, Thanksgiving was on Nov. 28.

Mulpuru said shipping networks could suffer from delays again because of the high volume of online sales. In 2013 UPS and FedEx both reported delays because of overloaded systems, poor weather and the shortened holiday period.