As Pope Francis arrives in the U.S. for a six-day visit, Catholic churches across the country have high hopes that his stopover will reinvigorate and offer fresh inspiration and spiritual guidance to their congregations.
But when it comes to the church's approach to receiving donations, its failure to adapt to easy online and mobile payment options means it is missing out on billions of dollars and suffering a "30-year dramatic downward slide," experts warn.
Some parishes, which still encourage members to give by cash and check, are missing out on hundreds of thousands of dollars every year said Patrick Coleman, CEO of online giving platform, GiveCentral, which has a client base that is 80 percent Catholic churches.
"We see that between check givers and online givers the average amount of giving over an entire year period is 35 percent more than those that give via check and about 90 percent more that give via cash," he told CNBC.
Coleman, who is based in Chicago, said in the state of Illinois alone, only around 30 percent of Catholic parishes are communicating with congregations well about giving and offering a number of ways for their donors to give.
"If they all followed the same pattern of even just a monthly email going out we would actually expect that giving in Illinois just in the Catholic community could actually go up by about $75 million and that is one state alone. So what this means across the country is actually billions," Coleman said.
Religious causes in the U.S. received $114.9 billion in 2014, a 2.5 percent increase on the previous year in current dollars, but when adjusted for inflation this comes in at just 0.9 percent growth according to data published by Giving USA earlier this summer.
"Although 2014 donations reached a new high of $114.90 billion, and, as always, (religion) accounted for the largest percentage of donations, the fact is, this category is continuing its 30-year dramatic downward slide as a share of total giving. In fact, it has dropped from 53 percent of all donations in 1987 to 32 percent of the total in 2014," the report found.
Coleman said for churches willing to put in just five-10 hours a month in engaging with its donor community through email or social media, it can repay itself by "500 or 1,000 percent" in terms of gifts.
Pope Francis has put a "much higher emphasis" on how global economics affects the poor than previous pontiffs according to Eric LeCompte, executive director of charity Jubilee USA that lobbies for a fairer economic policies and financial reforms to benefit the poor and acts as an adviser to the Vatican on issues surrounding the economy.
Global recession and poverty seen in major Catholic hubs across the globe has naturally dented some churches' coffers, but he stressed that the pope was more concerned about issues such as tax havens, corporate tax avoidance, illicit financial flows and corruption than donations.
"Well there is no doubt when you look at the island of Puerto Rico, an island of 4 million people, in the past few years alone because of the economic crisis, 500,000 people left," LeCompte told CNBC.
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"Half a million people and for a Catholic island like Puerto Rico, when people aren't in the pews they are definitely feeling that in the alms bucket, so I think that is a reality. But I think the church's concern is primarily on tax trade issues – so many people are living in poverty as a result of these policies that are legalised and put in place," he said.
Shrinking church attendance across the U.S. has also been hard ignore, with data showing the share of U.S. Catholics who reported attending Mass at least weekly fell by nearly half – from 47 percent to 24 percent – between 1974 and 2012, according to the General Social Survey (GSS).
The pope's visit comes ahead of the start an "extraordinary jubilee" year for the church commencing in December, a special year called by the church to receive blessing and pardon from God and to forgive debts.
The Catholic church calls jubilee years every 25 or 50 years and has also called special jubilee years from time to time, known as extraordinary jubilee years.
LeCompte, who attends meetings with the pope on occasion said he was resolute that the church must do everything it can to convince world leaders to act on world poverty.
"I have heard him say very clearly in meetings, that if the Catholic church is unable to convince world leaders to do everything they can to create a more sustainable economy, to address poverty and inequality, he thinks the Catholic church should sell everything and give it to the poor. I don't think that will actually happen, but that is how strongly he is making these statements," he added.