Online advertising spending in the United States topped $9.6 billion during the first quarter, up about 15.6% from $8.3 billion during the same quarter a year ago, according to the Interactive Advertising Bureau, a trade group for sellers of online ads.

The $9.6 billion spending sets a record for Q1 spending, the IAB says. It did not break out spending by ad type. “This first quarter milestone clearly illustrates that marketers recognize that digital has become the go-to medium for all sorts of activities on all sorts of screens, at home, at the office and on-the-run,” says Randall Rothenberg, President and CEO, IAB.

Spending decreased 6.8% quarter over quarter, though Q4 spending is routinely higher than Q1 spending due to major ad spending during the holiday season. Q4 2012 spending topped $10.3 billion.

In 2012, retailers accounted for 20% of all online ad spending, more than any other industry, according to a full-year digital ad spending analysis the IAB released earlier this year. Full-year spending on digital ads in 2012 reached $36.6 billion.