Russians are drinking less -- at least officially.

The country's consumer protection agency said Tuesday that Russian adults drank an average of 10 liters of pure alcohol in 2016, 33% less than they consumed in 2009.

That compares to a global average of 6.2 liters, according to the World Health Organization.

But the decline is not necessarily good news. Analysts say that some of the drop may be attributable to increased consumption of cheap, illegal alcohol that doesn't show up in official statistics.

Illicit vodka now accounts for 30% to 50% of all alcohol sales in Russia, according to market research firm Euromonitor International.

Georgij Grebinskij, a lead analyst at Euromonitor, said that higher taxes and a weak domestic economy are to blame for increased consumption of illegal booze.

Related: Global alcohol sales fall for first time in nearly 20 years

The Russian government has been trying to discourage heavy drinking. It has raised alcohol taxes, banned advertising and introduced more regulations to curb excessive drinking.

Euromonitor says the country's official alcoholic drinks market declined by an average of 5% each year between 2009 and 2016. But consumption of moonshine has spiked, especially since international sanctions and low oil prices hit real incomes.

"Stating that consumption of alcohol in Russia decreased by a third would not be entirely correct -- we rather observed redistribution of spending from legal to illicit alcohol," Grebinskij said.

Related: Putin cracks down on moonshine amid poisoning crisis

President Vladimir Putin ordered his government to get tough on illegal alcohol last year after dozens of people died in Siberia. They were killed after drinking a herbal remedy containing poisonous methanol.

The WHO says about one in three Russian men suffers from an alcohol use disorder, and about one in six is dependent on alcohol.

A study published in The Lancet in 2014 found that a quarter of Russian men die before the age of 55, most because of high alcohol consumption.