The combined minimum net worth of all of the members of the U.S. Congress is a whopping $2.1 billion, up more than $150 million over last year, making the average net worth of America’s senators and congressmen at least $3.9 million.

Every year since 1990, Roll Call, a Capitol Hill news publication, has dug into the financial disclosures of every member of Congress to determine the 50 richest members. But this year Roll Call ranked every member for the first time.

According to Roll Call, there are at least 188 millionaires in Congress, which makes up about a third of the legislative branch of the federal government. The median net worth in Congress is at least $456,522.

“At least,” because the way financial disclosures are made makes it difficult to accurately assess the net worth of the different members.

Roll Call explains:

The actual reported wealth of Congress would be significantly higher if Congress required members to disclose all of their assets and to disclose them with precision.

But assets and liabilities are disclosed in broad ranges — such as $1 million to $5 million — or more than $50 million, obscuring Congress’ true wealth. Lawmakers have the ability to get more specific in their filings, but few do.

Disclosure rules also require lawmakers to list mortgages, which count against net worth, but not home values, which would be one of the biggest assets of many members.

Non-interest-bearing bank accounts also do not have to be disclosed, no matter the value, nor do personal assets such as cars or home furnishings.

One thing we know for certain is that the average member of Congress is much richer than the average American. The median household net worth of the general public is $68,828, according to the latest Census Bureau statistics (2011). The median net worth in Congress is at least $456,522.

So how did Alabama’s senators and congressmen stack up?

The Yellowhammer State’s delegation has a total net worth of at least $9.62 million, which comes out to an average of $1.07 million per member, but a median of $320,000.

In the graph below, you can see each member’s minimum net worth as calculated by Roll Call, along with their rank across all of Congress.

For the second year in a row, the richest member of Congress is Rep. Darrell Issa (R-Calif.), the chairman of the House Oversight Committee, whose net worth is at least $357.25 million.

To check out the full list of the richest members of Congress, head over to Roll Call.

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