True story. It was revealed by SOS Alarm, which operates Sweden's emergency telephone line 112 (the equivalent of for example 911 in the US or 999 in the UK) in the run-up to Christmas.

“The Donald Duck effect is well-known to our operators, who find that the whole of Sweden calms down for a while. Far fewer people are out and about or going somewhere by car. It puts a temporary dent in the number of accidents and means fewer people call 112 that particular hour,” said Helena Söderblom, press officer at SOS Alarm, in a statement on Wednesday.

In 2015 the number of calls to the emergency number dropped by 16 percent between 3pm and 4pm compared to three hours before and after, according to SOS Alarm statistics. In 2013 the effect was even more noticeable, with a 26 percent drop in emergency calls registered.

Swedish Christmas celebrations are organized around the Donald Duck-centered Christmas special 'From All of Us to All of You', known in Swedish as 'Kalle Anka och hans vänner önskar God Jul' ('Donald Duck and his friends wish you a Merry Christmas') and has been shown at 3pm on Christmas Eve every year since 1959. Don't even think about recording it to watch later.

A total of 3.439 million Swedes watched the show in 2015. The record in the past two decades was in 1997 with 4.32 million viewers. This in a country with a population just shy of ten million.

“The Donald Duck effect shows how much impact our actions and behaviour have on for example the number of accidents and violent crime in society,” said Söderblom.

The decrease in 112 calls during 'Donald Duck hour'

2011: 20 percent

2012: 23 percent

2013: 26 percent

2014: 20 percent

2015: 16 percent