Russian President Vladimir Putin has released documents that appear to show he had an income of almost 5.8 million rubles (about $187,000) in 2012.

That figure was included in tax reports uploaded to the Kremlin's website earlier this week — part of a transparency obligation for Russian officials that began last year.

However, there's plenty of reason to doubt Putin's official claims.

According to the documents, Putin lives a relatively spartan life. The Russian president owns a plot of land, an apartment and a garage. He is in possession of three cars — two Soviet-made Gaz cars and a Niva SUV. His rarely-seen-in-public wife, Lyudmila, is said to own no property and have an income of less than $4,000.

To put that in context, the salary for the job of U.S. president is $400,000. Barack Obama's net worth was estimated to be between $2.8 million and $11.8 million in 2010.

Putin's own wealth has long been a subject of speculation. Some reports of his net worth are incredibly high, with one suggesting it may be an enormous $40 billion.

The most fantastic estimates go as high as $70 billion. That figure which would make Putin the richest man on earth.

His lifestyle certainly seems more akin to that of a richer man. He is said to have access to a fleet of vehicles worth $1 billion, has been spotted wearing watches worth at least $687,000 at retail, and he is rumored to have been building a private palace on the Black Sea worth $1 billion since 2006.

Putin's income announcement comes in the middle of the Kremlin's highly publicized battle against corruption amongst the Russian political elite. The Russian government is reportedly planning to audit every single government employee, and new laws will soon ban officials from having accounts and assets abroad.

Other politicians also had to declare their own assets and incomes.

First Deputy Prime Minister Igor Shuvalov, the government's spokesperson on the economy, revealed he had a huge income of 448.4 million rubles ($14.4 million), AFP reports. He has been forced to issue a statement explaining that none of his wealth breaks the law.