Christianity is experiencing an unprecedented boom on the African continent and now accounts for more than half of Africa’s total population, while Christian affiliation and practice continue to ebb in Europe, signaling a major demographic shift in global Christianity.

An article in the Christmas issue of the Economist lays out the sobering statistics of European Christianity, while holding up the remarkable growth of the Christian faith among Africans.

Christianity is experiencing more rapid growth in Africa than anywhere else on the planet, including Asia and Latin America. In 1910 less than 10% of Africans identified as Christians, whereas today 55% of the population is Christian. And while in 2015 Europe still has the largest Christian population of any continent at just over 575 million, Africa is projected to overtake it by 2025.

The growth of Christianity in Africa averages 2.78% each year, while Europe’s growth rate languishes at 0.16%, meaning that while Africa becomes more and more Christian, Europe becomes less so.

The striking growth of Christianity in Africa is not merely a question of religious affiliation, but is reflected in actual religious belief and practice. The Economist reports that 90% of self-identified Christians attend church regularly across the five sub-Saharan African countries for which data are available (Ghana, Nigeria, Rwanda, South Africa and Zimbabwe), making African Christians the most devout in the world.

Religious practice among European Christians, on the other hand, is significantly lower, and falling year by year. In France and Sweden, only one in ten adult Christians attend church services at least once a month.

In traditionally Catholic Ireland, nearly 90% of adult Catholics attended Mass every week in 1984, but by 2011 the number had plummeted to just 18%.

In Germany, more than 400 Roman Catholic churches and more than 100 Protestant churches have been shut down since 2000, with another 700 Roman Catholic churches scheduled for closing over the next several years. Religious practice among Germans is falling year by year and just 12.3% of Catholics regularly attend Church services, according to the German conference of bishops.

Christianity’s glacial growth in Europe combined with massive immigration of non-Christians is resulting in a steady decrease in the percentage of the continent identifying as Christian. Only about a third of Europeans who call themselves Christian say they go to church services once a month or so.

Many theories exist to explain the exceptional growth of African Christianity. One relates to the elevated number of Christians martyred on African soil in the last century. It was the early Christian apologist Tertullian, himself an African from Carthage, who coined the phrase “the blood of martyrs is the seed of Christians” (sanguis martyrum semen Christianorum), suggesting that Christians’ witness to the point of death drew many more faithful into the Church.

Without counting the 600,000 or so Christians who died in the genocidal conflicts in Rwanda and Burundi, approximately 1.8 million Christians died as martyrs in Africa in the 20th century alone.

As the Christian Church celebrates on December 26 the feast of Saint Stephen, considered the first Christian martyr or “proto-martyr,” she looks to Africa for her future.

Follow Thomas D. Williams on Twitter @tdwilliamsrome