It's a statistic tourists in Rome often hear while gazing at centuries of glorious architecture: The eternal city contains more than 900 churches.
Other statistics will affect those holy sites in the future.
For example, a record-low 458,151 births occurred last year in Italy. The fertility rate -- currently 1.32, far below a 2.1 replacement rate -- is expected to decline again this year. Meanwhile, the number of marriages fell 6 percent, between 2016 and 2017, and religious marriages plunged 10.5 percent.
"Currently we are at a roughly terminal stage. It would not be bad if the Church, the first to pay the price, would understand this and get moving," noted demographer Roberto Volpi, quoted in the newspaper Il Foglio.
Thus, lots of Rome's 900-plus churches will be empty in the next generation or so.
That was the context of remarks by Pope Francis during a recent Pontifical Council for Culture conference, a gathering with this sobering title: "Doesn't God dwell here any more? Decommissioning places of worship and integrated management of ecclesiastical cultural heritage."
Francis stressed: "The observation that many churches, which until a few years ago were necessary, are now no longer thus, due to a lack of faithful and clergy, or a different distribution of the population between cities and rural areas, should be welcomed in the Church not with anxiety, but as a sign of the times that invites us to reflection and requires us to adapt."
The church has problems, but there are "virtuous" ways to deal with them, he said. Bishops in Europe, North America and elsewhere are learning to cope.
"Decommissioning must not be first and only solution … nor must it be carried out with the scandal of the faithful. Should it become necessary, it should be inserted in the time of ordinary pastoral planning, be proceded by adequate information and be a shared decision" involving civic and church leaders, he said.
Pope Francis appears to be advising Catholics not to worry too much as "For sale" or even "Property condemned" signs appear on lots of sanctuaries in some parts of the world, said Phil Lawler, a conservative journalist with 35 years of experience in diocesan and independent Catholic publications.
"The sentence that triggered me was when the pope said we shouldn't be ANXIOUS about all of this," he said. "It's like he's saying, 'Don't worry, it's not all that bad.' … He says that at the same time that he says we're going to be closing lots of churches because we don't have enough Catholics to fill them and priests to serve in them. …
"That's stunning, to me. When a congregation gets smaller, that can change in a few years. When you close a church -- it's gone."
It's easy to focus on diocesan decisions about where churches close and where new facilities are built. Concerned Catholics need to watch other trends, said Lawler.
Weddings and baptisms are crucial. Georgetown University's Center for Applied Research in the Apostolate reports show there were 426,309 Catholic weddings in American churches in 1970, compared with 144,148 in 2017. There were nearly 1.1 million infant baptisms in 1970 and 660,367 in 2017, while America's population soared. Weekly mass attendance fell from 48 percent to 23 percent during that same era.
Pew Forum research in 2015 found that for every convert, the church loses more than six Catholics -- the highest exit rate of any American flock.
This is old news. "What matters is how the church responds," said Lawler.
After all, an emerging German theologian predicted -- in 1969 -- that hard times were ahead.
"From the crisis of today the Church of tomorrow will emerge. … She will become small and will have to start afresh more or less from the beginning. She will no longer be able to inhabit many of the edifices she built in prosperity," said Father Joseph Ratzinger, who would eventually become Pope Benedict XVI.
The future will not belong, he said, to those who "accommodate themselves merely to the passing moment." A smaller, crystalized church will "make much bigger demands on the initiative of her individual members."
Ratzinger concluded: "I am equally certain about what will remain at the end: not the Church of the political cult, which is dead already, but the Church of faith."