Open government advocates had high hopes at the dawn of the Obama administration. Shortly after taking office, the president signed an executive order instructing federal agencies to embrace transparency. But talking about government data is much easier than actually getting useful data in the hands of the public. Almost three years later, the mundane reality hasn't always lived up to the lofty ambitions.

The Cato Institute has been conducting a comprehensive audit of online government transparency. Building on a September white paper, the think tank has turned its focus to government spending, cataloging the many types of spending-related data the government could be releasing, and then grading Congress and the executive branch on their success in releasing each data category in machine-readable, structured formats. Unfortunately, the government's report card has a lot of "incompletes."

For spending data to be meaningful, the government needs to release more than raw dollar figures. It also needs a standardized scheme for specifying which units of government are spending the money and which entities are receiving it. Unfortunately, the federal government has not made its "org chart"—the hierarchy of departments, agencies, and bureaus—available in a structured format. Such a model exists, but it's only available as an opaque PDF.

"This fruit is hanging so low that a gopher could snack on it without leaving its hole," quips the report's author, Jim Harper.

But other aspects of spending transparency won't be so easy to achieve. The feds do have a standardized scheme for cataloguing companies that are the recipients of federal funding. Unfortunately, this system, known as the DUNS number, is a proprietary product created by Dun and Bradstreet. Ideally, the government should create an open replacement for the DUNS number, but that's going to be a slow and expensive process.

Ars Technica talked to Kaitlin Lee, a developer at the Sunlight Foundation, about the report. She shared Harper's assessment, calling the transparency of spending data "pretty terrible."

However, she argued that Cato left out one important category of data, so-called tax expenditures. These are targeted tax breaks that reduce the amount of money flowing into the treasury. While tax breaks aren't technically spending, Lee argued that they're economically equivalent to government spending and should be taken into account in any effort to understand the federal budget.

Harper says he plans to release additional reports on the transparency of other parts of the government, including taxes. He also plans to periodically update the grades to reflect the government's progress—or lack thereof—toward transparency. First up will be a re-assessment of the transparency of the legislative process, a subject he first tackled back in September.

Disclosure: I'm an adjunct scholar at the Cato Institute, an unpaid position. I wasn't involved in the preparation of the transparency report covered in this article.