Consumers are making more online purchases this holiday season but spending less per purchase, according to data released this week by Chase Paymentech Solutions LLC.

The Dallas merchant processor said that the number of online card purchases moving through its systems is up 28% from last year but the total spent grew 13%. The difference reflects a 13% drop in the average ticket amount, the first decline measured by the company's annual Cyber Holiday Pulse Index.

Dec. 2, the Tuesday after Thanksgiving, was the busiest day for online shopping the Paymentech index has ever tracked, with transaction volume up 55% from the same day last year and total sales up 47%.

This was a departure from past years, when the Monday after Thanksgiving, sometimes called Cyber Monday, was the top day for online holiday shopping.

Paymentech said this fits with a larger trend in which many shoppers are expected to procrastinate when it comes to making holiday purchases.

Data from Forrester Research cited by Paymentech showed 21% of consumers expect to make last-minute purchases this year and retailers anticipating strong online sales through Dec. 19, the Friday before Christmas. Online sales will probably slow after that because of the time required to ship a purchased item.

Paymentech processes payments for more than half the 500 largest online retailers. The Cyber Holiday Pulse Index tracks purchases at 25 of the top 150 online merchants.