Excerpt:
Members of the public in the Netherlands and other European states widely overestimate the size of their Muslim populations, according to an Ipsos Mori poll.
The average Dutch estimate is that 19% of the population of the Netherlands in Muslim, but the real figure is just 6%. They also expect the Muslim population to grow to 26% by 2020, while official estimates say Muslims will make up just 6.9% of the Netherlands' population by then.
The widest gap was in France, where the average estimate of the size of the Muslim population was 31%. In reality, the actual Muslim population stood at 7.5%, according to figures from the Pew Research Centre.