Marijuana sales reached over $1 billion in the first eight months of 2017 JACK GUEZ/AFP/Getty Images

Cannabis sales in the US state of Colorado have eclipsed $1bn (£750m) so far this year.

In the first eight months of 2017, marijuana sellers made a total of $1.02 billion in medicinal and recreational sales, according to The Cannabist.

Sales of the soft drug are up by 21% compared with the same period in 2016, when cannabis sales totalled $846.5m.

Recreational cannabis became legal in Colorado in 2012, 12 years after the use of medicinal marijuana was legalised. The sale and possession of cannabis is legal in seven other US states: Nevada, Maine, Washington, California, Massachusetts, Alaska and Oregon.

Colorado has the highest youth cannabis consumption rate, 74% above than the national average, according to the Rocky Mountain high intensity drug trafficking area report.

When cannabis was legalised in 2012, state officials promised high tax revenues. Cannabis sales brought in nearly $73.5m in tax revenues in the first seven months of this year.

In 2014, experts predicted that sales would deposit an annual $70m into state coffers, according to The Guardian. But that year the state only collected $44m in marijuana taxes.

The rise in cannabis sales in 2017 has been attributed to a growing social acceptance about using marijuana.

"I attribute it to ... more and more people ... comfortable with the legalisation of marijuana," said Tyler Henson, president of the Colorado Cannabis Chamber of Commerce, as quoted in The Guardian. "They don't see it as something that's bad for them."

"People who would never have considered pot before are now popping their heads in," added Tim Cullen, CEO of Colorado Harvest Company.

58% of Coloradans support keeping the soft drug legal, while 38% oppose the idea, according to a Quinnipiac University poll published in February 2017.