We developed the LIE index to track the variation in sleep patterns across the world.

The worst sleepers are mainly in Asian countries.

Per weeknight, Japan, South Korea and India average just over six hours.

Whereas in northern European countries like Finland, Ireland and the Netherlands, people log a solid seven hours a night, as they do in Australia and New Zealand.

Lack of sleep is a serious business.

Staying up for 20 hours has the same effect on your reasoning as drinking a bottle of wine.

And one study found lack of sleep cost Japan nearly 3% of its annual GDP, largely due to lower productivity.

What time people hit the sack and get up in the morning also varies by country.

South Africans go to bed earliest, before 11; while Japan and Russia have some of the latest bedtimes, turning in after midnight.

But in Japan, people are up nearly an hour earlier than in Russia.

Researchers think these variations could be connected to work culture.

And as two weeks of six-hour nights has the same effect on your brain as pulling two consecutive all-nighters, it's a good idea to try to get the lights off earlier.