CNS PHOTO| OSWALDO RIVAS, REUTERS
Girls attend First Communion in Nicaragua: In two decades time, the Catholic population of the Americas has increased more than 25 per cent.
The percentage of Catholics practising their faith is declining almost everywhere around the globe. Almost all bishops report it, but it's difficult to prove statistically.
Each year, the Vatican's own statisticians compile mountains of data about the number of Catholics, Baptisms, priests and religious, weddings and annulments in each diocese and country.
The numbers illustrate trends over time, but many factors lead to the variations, said Enrico Nenna, the chief statistician in the Vatican's Central Office for Church Statistics.
"It's very difficult to quantify Catholic practice, although many have tried with many different formulas," he said. "The only way to get an accurate picture of religious practice would be to carefully choose a cross section of the population, do a census, and then conduct interviews repeated over time."
The number of Baptisms and Catholic weddings reported around the world also are influenced by too many factors to be unquestionable indications of Catholic practice, Nenna said.
For example, the declining number of Catholic weddings worries the Church because it indicates, at least in part, that some Catholics are forgoing a sacramental marriage in favour of a civil union or are simply living together, he said.
But it also reflects that people around the world are marrying older and, especially in a time of economic crisis, are waiting to start a family of their own.
Similarly, he said, while a declining number of infant Baptisms can indicate a weaker faith commitment among a generation of new Catholic parents, it also is a natural result of declining birthrates.
The working document for the upcoming world Synod of Bishops on the new evangelization contains more than a dozen references to a "weakening of faith" or "declining practice," but it includes no numbers.
The document was written on the basis of the responses to a Vatican questionnaire submitted by 114 bishops' conferences, 26 Vatican offices and the international unions of superior generals of religious orders.
All the responses, the document said, described "a weakening of faith in Christian communities, a diminished regard for the authority of the magisterium, an individualistic approach to belonging to the Church, a decline in religious practice and a disengagement in transmitting the faith to new generations."
At the same time, the Vatican's Statistical Yearbook of the Church reports that the number of Catholics in the world – almost 1.2 billion – is holding steady at about 17.5 per cent of the world's people.
The number of priests has shown a steady increase since 2000, and the number of seminarians has gone up each year for the past 15 years.
For Nenna, the reports to the synod planners and the contents of the statistical yearbook are not necessarily at odds. The synod document is based on observation, while the yearbook is based on a census each bishop is required to fill out annually.
One problem with the census, Nenna said, is that not every bishop is careful filling out the forms and, in most situations, Catholics who stop going to church do not formally leave, so they are still counted as members.
Still, the statistician believes there are signs of declining religious practice in the data he collects.
For example, figures on the number of First Communions and Confirmations point to a decline, particularly in Europe, where Pope Benedict and others already have sounded the alarm.
In the 20 years between 1990 and 2010, the global Catholic population grew from 928.5 million to almost 1.2 billion, a 29 per cent increase.
However, that increase is not mirrored in the number of First Communions or Confirmations reported.
The number of Confirmations rose only 10 per cent to 8.8 million in 2010, the yearbook says.
The situation is worse when looking at the breakdown of the 10.7 million First Communions reported. Over the past two decades, the number of First Communions dropped so much in the Americas, Oceania and Europe that it caused a decrease of five per cent in the global numbers.
Even in Africa and Asia, where the number of First Communions increased over the past 20 years, the increase did not keep up with the rise in the total number of Catholics there.
The Catholic population of Africa, for example, increased by 109 per cent, but First Communions went up by only 21 per cent.
The numbers could reflect a change in reporting methods – especially in places where many adults enter the Church and receive Baptism, Confirmation and First Communion at the same Mass – but they still demonstrate the bishops' concerns have statistical weight behind them.
The synod will bring representatives of the world's bishops' conferences to the Vatican for three weeks in October. Its goal is to energize Catholic communities and encourage outreach to those who, "despite being baptized, have drifted from the Church and Christian practice," the synod working document says.