Sick days are costing UK companies more than £23bn a year and the World Cup and Wimbledon could be making the problem even worse, according to professional services firm PwC.

The study, which surveyed more than 2,000 people in the UK, also found that a large proportion of the sick bill is preventable as one in three British workers admit to having pulled a "sickie" - a phenomenon which is costing businesses £9bn ($15.4bn, €11.3bn) a year.

PwC revealed that the most popular reasons for why people pulled a sickie are hangovers (32%), to watch a sporting event (8%), being bored with your job (26%), interviews (26%) and Mondays (11%).

In addition, one in 10 respondents said they have lied to take time off work due to good weather.

"The combination of major sporting events such as the World Cup and Wimbledon may mean that the temptation to lie to take time off work to watch sport is too much for some," said Jon Andrews, head of human resources consulting at PwC.

Companies could easily reduce the knock-on impact on their employees' productivity levels by offering flexible working or allowing them to watch key matches in the office."

PwC analysis of over 2,500 global companies shows that the UK's overall sickness bill (including genuine and made-up illness) has fallen to £23bn from £29bn a year ago.

But despite this positive trend, UK workers still take nearly triple the amount of sick days as their global counterparts in Asia Pacific (2.8 days) and nearly double the US (3.8 days).

PwC explained that most industries have reduced their sickness levels compared to a year ago apart from technology, chemicals and utilities companies.

Retail and leisure, services sector and finance companies report the lowest levels of sickness, according to the research.