The proportion of people with no religious affiliation is approximately between 37% and 43%. The secularization trend in Dutch society is not only reflected in a significant reduction in the number of people who follow a religion, but also in a decline in the level of devotion among religious believers. This is particularly evident among Catholics. Catholic devotees in the Netherlands were once the most devout believers in Europe. Survey results prior to 1960 indicated that among Dutch Catholics, 90% regularly attended Mass at church.