Newspaper revenue from print ads is falling $7 for every $1 gain in digital advertising, the Pew Research Center said Monday.

A study by the center's Project for Excellence in Journalism of 38 newspapers found that even though total digital advertising revenue from those newspapers rose on average 19 percent in the last full year, it didn't come anywhere close to making up for the dollars lost as a result of an average 9 percent decline in print advertising.

Executives at the 13 companies involved in this report confirmed that closing the revenue gap remains an uphill and existential struggle, Pew said in a statement.

The most optimistic projections saw digital gains overcoming print losses within a few years; the most pessimistic held that it would never occur. A number of executives said they did not know when it might happen.

The study reveals an industry that has not yet moved very far down the road toward a business model to replace the once-thriving legacy model, a model whose revenue is down more than 40 percent in the last decade.

Only 40 percent of the papers that provided data said targeted advertising is a major part of their sales effort, according to Pew. Even though many newspapers aren't focusing on it, smart or targeted digital advertising -- in which ads are customized based on consumer online behavior -- is expected to dominate local digital revenue by 2014.

The number of print-focused sales representatives outnumbered digital-focused reps by about 3-1, despite most newspapers focusing on digital sales training and hiring sales people with digital experience.

But the industry's sales force remains more focused on print, reflecting the fact that print ad revenue, which is shrinking, still makes up the bulk of the overall revenue, on average 92 percent, in the study's sample, Pew said in a statement.