By our calculations, 2001 was the last time there was near-parity between the money spent on lobbying and the money spent on salaries for members of Congress and their staff. That year, salaries and compensation for the entire legislative branch was $1.6 billion, according to the Office of Management and Budget's "Object Class Analysis." Lobbying organizations, meanwhile, spent $1.64 billion -- a figure which increased steadily until 2010. (That number comes from the Center for Responsive Politics, which compiled data from the Senate Office of Public Records.)

Since then, the gap has widened, with significantly more money spent on the the lobbyists and than the lobbied. (Data for 2014 is an estimate from the 2015 document.)

On Monday, Vox's Ezra Klein wrote about a subset of those lobbyists: Corporations -- which according to his sources were spending $2.6 billion alone trying to influence what happens on Capitol Hill. The subtle distinction between corporate lobbyists and other lobbying clients pales when it comes to Klein's strongest point: Members of Congress rely on lobbyists to provide information that, many would argue, would be better coming from sources not paid by biased interests.

For example, that data could be provided by staff. The exact number of staffers working on Capitol Hill varies, which is to be expected given that it is essentially 535 individual departments that do their own hiring and firing, bolstered by committees and staff that operate the same way. The Sunlight Foundation gives a range of 7,000-8,000 staffers on the House side alone. There are fewer Senate offices but each may have a larger staff than the 18-plus allotted to members of the House. (The Congressional Research Service produced a nice look at how compensation works on both sides of the Hill last year.)

Compare that with the 11,781 people registered to lobby Congress in 2014, per CRP -- a figure that was actually down somewhat from previous years. (As the Washington Examiner noted earlier this month, the number of lobbyists correlates to how much spending is happening in Washington.)

Part of the reason is that it's impossible to have staff knowledgeable on every subject, particularly in an organization as complex as the United States government. "It's in [the] vast gap between how many issues members of Congress — and their staffs — can know and care about, and how many issues they're being asked to vote on," Klein writes, "where lobbying is most powerful." That's true. And it's not necessarily a bad thing, either.

There's another point worth making: Overall spending on the legislative branch -- which includes facilities, travel, and contracted services -- far exceeds what is spent on lobbying.

(The spike in 2010 is a function of a one-year increase in a line item titled "refunds." This being a mystery to us, we reached out to OMB for clarification and have not heard back.)

The problem in the system is not necessarily that there are more lobbyists than Hill staffers or more spending on lobbying than on Congress. The problem is that lobbying is inherently biased, and the information provided to members of Congress is necessarily incomplete -- and might not have a counterpoint. And it's not clear that there's a viable alternative.