Suffolk singer Ed Sheeran’s best selling single of last year has been cited in a study which found pop songs are becoming slower and “sadder-sounding”.

The study, published by the American Psychological Association, revealed that for 87% of 2017, the UK number one single was in a minor key – up from 62% the previous year and only 29% in 2015.

Research carried out by Popbitch, the celebrity and music website, noted that whereas minor key number ones, including Ed’s Shape of You, had lengthy chart-topping periods, those in a cheerier major key tended to occupy the top spot for just one week.

The study also found songs were becoming slower with the average beats per minute for a number one single falling below 100 for the first time since 2002.

It concluded: “Popular music has, in general, become sadder-sounding over time, with an increasing use of minor mode and slower tempo”.