Faith Matters is a Muslim think tank. Their report can be downloaded here.
Via the Independent:
The number of Britons choosing to become Muslims has nearly doubled in the past decade, according to one of the most comprehensive attempts to estimate how many people have embraced Islam.
Estimating the number of converts living in Britain has always been difficult because census data does not differentiate between whether a religious person has adopted a new faith or was born into it. Previous estimates have placed the number of Muslim converts in the UK at between 14,000 and 25,000.
But a new study by the inter-faith think-tank Faith Matters suggests the real figure could be as high as 100,000, with as many as 5,000 new conversions nationwide each year.
By using data from the Scottish 2001 census – the only survey to ask respondents what their religion was at birth as well as at the time of the survey – researchers broke down what proportion of Muslim converts there were and then extrapolated the figures for Britain as a whole.
In all they estimated that there were 60,699 converts living in Britain in 2001. With no new census planned until next year, researchers polled mosques in London to try to calculate how many conversions take place a year. The results gave a figure of 1,400 conversions in the capital in the past 12 months which, when extrapolated nationwide, would mean approximately 5,200 people adopting Islam every year. The figures are comparable with studies in Germany and France which found that there were around 4,000 conversions a year.
Fiyaz Mughal, director of Faith Matters, admitted that coming up with a reliable estimate of the number of converts to Islam was notoriously difficult. "This report is the best intellectual 'guestimate' using census numbers, local authority data and polling from mosques," he said. "Either way few people doubt that the number adopting Islam in the UK has risen dramatically in the past 10 years."