The percentage of people who believe in hauntings and ghosts are much lower in Scandinavian countries than in other areas of Europe and the U.S. (10-15% vs 30-40%)
But the popularity of ghosts is growing.
In February 2017 the Swedish Society for Parapsychology announced the launch of a study into ghostly experiences occurring in domestic dwellings. See more here:
The survey results will most likely appear in a professional journal of parapsychology.