Around 1.6 million women and 400,000 men — or about 5 percent of the Italian population — were molested as minors, according to the results of a sexual harassment survey published Tuesday.

Official figures from Italy's statistics agency, Istat, said most of those targeted did not know their abuser. However, almost 15 percent of female victims, and 7.4 percent of males, said they were molested by a relative. In 4.2 percent of cases, boys said they were abused by a priest or nun.

The anonymous survey found that a significant proportion of those who were abused under the age of 18 didn't speak up — about 62 percent of male victims and 43 percent of female victims kept the ordeal to themselves.  

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In over 60 percent of cases the abuse only happened once, while a quarter of the victims said it was repeated up to five times.

The data is based on a nationwide sample of 50,350 individuals interviewed in 2015-2016.

Sexual harassment in decline

The Istat study, which is conducted every five years, also reported that just under 9 million women in Italy had faced some form of sexual harassment in their lifetime, including 3.1 million in the last three years.

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Almost all women surveyed said they had experienced exhibitionism and stalking by men. Around 1.4 million said they had suffered unwanted touching at work or sexual blackmail in the workplace, and in over 80 percent of cases they did not report it.

The agency added, however, that there had been a "significant decline" in cases, with the number of women suffering abuse dropping from 18.7 percent in 2008-2009 to 12.8 percent in the most recent survey.

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Istat also published data on sexual harassment against men for the first time. It concluded that 3.8 million men have been victims at some point during their lives, including 1.3 million in the last three years. But it found that the perception of physical harassment differed depending on the sex of the respondent: 76 percent of women considered it to be very or fairly serious, compared to 47 percent of men.

The Istat results were collected before allegations of sexual misconduct engulfed Hollywood movie producer Harvey Weinstein last year. Since then, millions of women around the world have come forward with stories of harassment and abuse, raising the profile of the problem in the workplace and broader society.