When it comes to the growth of secularism in Switzerland, the figures speak for themselves.
More than one in ten of the Swiss population – 810,000 people – claims "no religious affiliation", up almost 60 per cent on a decade earlier.
In fact they form the third-largest "religious group" in Switzerland after the Protestant and Roman Catholic churches, accounting for a little over 11 per cent of the population.
Equally significant is the number of people who gave no indication of their religious orientation in the most recent census: 315,800 – triple the number ten years earlier.
For Reta Caspar, spokeswoman for the Swiss freethinkers association, the sharp rise in the number of "non-believers" is proof that religion has become increasingly irrelevant, especially among younger generations.
Caspar claims more and more young people see churches as out of touch, because of their "outmoded" stance on issues such as abortion, homosexuality, contraception and evolution.
She says continuing revelations of child sex abuse scandals, notably involving Catholic priests, have also raised questions about "double moral standards".
"I think there is a general tendency that traditional religions with their rigid moral and dogma systems are not attractive any more," she said.
"I think younger people increasingly can no longer relate to what the church authorities are telling them."
Evidence of this can be seen in the 2000 census, which showed a substantial increase in the number of 20-39 year olds claiming no religious affiliation compared with ten years earlier.
A more recent publication paints an even bigger picture of secularism in Switzerland.
According to the Cambridge Companion to Atheism, published three years ago, up to a quarter of the Swiss population say they are "atheist, agnostic or non-believers in God".
But sociologist Claude Bovay, author of The Religious Landscape in Switzerland, a book that examined in depth the census findings, says the various statistics need to be treated with some caution.
He argues that those claiming no religious affiliation are not necessarily non-believers: they may have simply not found a spiritual outlet among the existing faiths.
But whatever the true extent of secularism in Switzerland, Bovay agrees there has been a clear drift away from the traditional churches.
He says religion has steadily been losing its influence over society since the 1950s and the gap has widened over the past 25 years with the growth of individualism.
"Institutions – and we have seen the same thing in politics and other areas – have lost control over their members," explained Bovay.
And then there is the family. According to Bovay, religion is no longer being passed down from the parent to child as it was in the past, and children are being allowed to decide for themselves at an earlier age.
With more young people turning away from religion and older believers dying off, Bovay expects the number of non-affiliated to increase for the foreseeable future.
"The Federal Statistics Office has tried to make projections on a strictly demographic basis, and the rate of growth which has been observed will remain the same or even increase slightly," he said.
A further increase of 60 per cent would put the number of non-affiliated near 1.3 million by 2010. Assuming an overall population of 7.4 million, that is close to one in five non-believers.
swissinfo, Adam Beaumont
Ecclesiastical law is decided by each of the 26 cantons and not at a national level.
Non-believers say this prevents them from becoming an effective lobby group.
Census figures from the Federal Statistics Office reveal a steady drift away from the big two: the Reformed Protestant and Roman Catholic churches.
Despite an increase in the Swiss population of 414,300 – or six per cent – between 1990 and 2000, these churches – in particular the Protestant church – saw congregations dwindle.
Meanwhile the number of people recording "no religious affiliation" rose from 510,900 to 809,800 – a jump of just under 60%. A clear trend emerged in the bigger cities.
The Swiss freethinkers association, which celebrates its 100th anniversary next year, comprises 55% atheists, 19% non-dogmatic theists, 18% agnostics and 8% pantheists.