Last year image exchange volume rose 97% from 2007, to a record 5.6 billion check images, The Clearing House Payments Co. LLC of New York said Thursday.

The 2007 growth rate was 376%, according to The Clearing House, which is owned by 19 large U.S. banking companies. Its SVPCO Image Payments Network enables banks to settle checks electronically.

Last year dollar volume rose 71%, to a record $8.5 trillion, and the number of institutions exchanging images nearly doubled, to 44, The Clearing House said.

Early adoption was driven by large banks that exchanged lots of checks with their trading partners, using software called a distributed traffic agent, which routes images directly for clearing and uses The Clearing House as the settlement agent.

But Susan Long, the senior vice president at The Clearing House who heads SVPCO, said in a press release that future growth is likely to come from a hosted version of the software that lets smaller institutions send encrypted images over a public Internet connection.

Most of the institutions connecting to the network already use the hosted connection, Ms. Long said.

"By using the Gateway DTA with an Internet connection, institutions can get all the advantages of being part of this network without the expense of installing a dedicated line and server," Ms. Long said.

"In 2009, we expect the Gateway DTA to be the network connection of choice for financial institutions and a key driver of growth, because institutions are more focused than ever on finding new ways to reduce costs."

The Clearing House expects this year's image volume to top 7.4 billion and its monthly dollar volume to reach $1 trillion by midyear, a spokesman said.