The West has no idea how many Muslims are in their countries

Western countries dramatically overestimate how many Muslims are in their countries, a survey by Ipsos Mori has found, with many people wrongly believing that the Muslim population is increasing “at an incredible rate”.

Perils of Perception, the survey company’s latest report, found that Britons believe that 15 percent of their current population is Muslim – when the real figure is only 4.8 percent, less than a third of the UK’s best guess.

By 2020, French respondents to the survey thought that 40 percent of their population would be Muslim – the actual projection is 8.3 percent

With regards to the future Muslim population, Britons thought that 22 percent of their population would be Muslim by 2020, when projections from the Pew Research Centre suggest Muslims will only make up around 6 percent of the British population by then.

But if Britain’s estimating capabilities were poor, they still fared better than their global counterparts.

France, for example, thought that an astonishing 31 percent of their current population were Muslim. The actual figure is just 7.5 percent.

By 2020, the French respondents to the survey thought that 40 percent of their population would be Muslim – when the actual projection is 8.3 percent, an increase of just 0.8 percent from the current level.

Germany, Italy, and Belgium were also all “massively out” regarding current Muslim population levels, and “greatly overestimate the growth in their Muslim population,” according to the survey.

Never to be outdone, Americans projected that a whopping 23 percent of their population would be Muslim by 2020 – compared with the actual projection of 1.1 percent.

But several Muslim-majority countries underestimated their Muslim populations.

Turkey has a Muslim population of 98 percent of the total, but Turks estimated on average that it was only 81 percent.

And Indonesia estimated its Muslim percentage as 80 percent, when it's actually 87.2 percent.