The Press Democrat this week will begin to charge for some of the content it produces online, joining a growing number of newspapers around the country asking readers to pay for digital content that was once free.

Readers who do not subscribe to the newspaper will have access to about 15 news articles per month for free, and after crossing that threshold will be prompted to subscribe to the print or digital versions of the paper. Press Democrat subscribers will continue to have access to all content, print or digital.

Some sections of the website, such as PD Preps, event listings and photo galleries will remain free of charge.

"I think we have real value in the content of this newspaper," said Steve Falk, CEO of Sonoma Media Investments, which owns The Press Democrat. "Simultaneously, we are following our readers to digital applications as more and more people appreciate the convenience of iPhones and iPads and tablets. But at some point we have to keep the journalism healthy financially, and the way to do that is to begin putting a value on the content."

Nationwide, 450 of the 1,380 daily newspapers have started or announced plans for some type of paywall or digital subscription service, according to the Pew Research Center's annual State of the News Media report. The report called 2012 a "tipping point" as many newspapers tackled the problem of monetizing their products online, often opting for a "metered" plan like the one The Press Democrat has chosen.

"The trend has been strong for two to three years now," said Rick Edmonds, media business analyst at Poynter Institute, a nonprofit school of journalism located in St. Petersburg, Fla. "There may be some out there that aren't working that well, but I think generally speaking it's successful, and it's certainly seemed to indicate something when Gannett put paywalls in at essentially all or nearly all their 80 community newspapers, which vary in size ... and they have been satisfied with their results."

News outlets have begun taking the step after years of declining advertising revenue. Print advertising revenue in newspapers fell to $18.9 billion nationwide in 2012, less than half of the 2005 total of $47.4 billion. Online advertising hasn't made up the difference, reaching $3.4 billion in 2012, up from $2 billion in 2005. Meanwhile, newsroom staffs have been slashed nationwide by 30 percent since a peak in 2000, according to Pew.

"The reporting that goes into the stories, and the cost to have quality stories and pay for those stories, and the photos and everything that goes with them, can't be paid for just simply through advertising," said Bruce Kyse, publisher of The Press Democrat.

At its peak, around 1995, the Press Democrat enjoyed circulation of more than 90,000 subscribers on weekdays and more than 100,000 on Sunday, Kyse said.

"Like every newspaper, we've lost print distribution as more people have gone online and digital to get their local information," Kyse said.

But as readers migrated online, subscriptions fell. At the end of March, The Press Democrat had a circulation of 55,898 on Sunday and 52,724 on weekdays, according to the Alliance for Audited Media, which tracks print and online subscriptions of news outlets.

"And while the size of the newspaper is smaller than it was, the newsroom has not contracted as quickly as the revenue has contracted, and we're determined to keep the investment in local journalism," Falk said.

Current subscribers to the newspaper will have unlimited access to the website after completing online registration. Digital-only subscriptions will be available for $1.99 for the first month and then $9.99 per month.

Like other news sites, if a reader finds his or her way to a Press Democrat story based through social media sites like Facebook or through search engines like Google, that first story will not count toward the user's monthly tally of articles. However, a second article that user reads will be counted toward their total.

"Most people won't see it immediately, because they won't notice until they start hitting the article limitation," Kyse said.

In the case of major breaking news stories, editors will have the flexibility to enable some articles to be freely available without a subscription, Kyse said.

The digital subscription only applies to The Press Democrat, not to other media entities owned by Sonoma Media Investments, including the North Bay Business Journal, The Argus Courier or The Sonoma Index-Tribune. Those websites will remain free, for now.

"We're not quite ready to get to them yet," Kyse said.

Traditionally, newspaper revenues were split with about 80 percent coming from advertising dollars and 20 percent from circulation. But The New York Times, which has a 2-year-old digital subscription program, reported its circulation revenue now exceeds its advertising revenue, according to the Pew Report.

Other newspapers of various sizes have been reporting success with paywalls, said Edmonds.

"It's an extra set of challenges when you're doing this on your own, as opposed to being part of a chain that's providing whatever institutional knowledge that the chain has and perhaps a common pattern for vendors and market research, but that's not insurmountable," Edmonds said.

"It's a place where it ought to work," Edmonds said. "If you produce a good amount of community news that's not readily available elsewhere, that's a sound basis for a paper and a sound basis for a paywall."