I wrote about this site and others in a post in July, Great Examples of US Government BI Transparency. Unfortunately, it turns out that it’s not so great, in that some of the data shown was completely false… (this is generally considered a reasonable baseline of things to avoid).
Seth gave the example of the graphic on the left below: “The Green and Purple segments are approximately equally sized even though the green segment should be 25% larger than the purple segment”. Thankfully the problem has now been corrected, and the site now shows what the chart should look like (with the data values now slightly updated) – see how much larger the “grants” area is now.
The problem turned out to be with the way the site calls the Google Chart API. The values passed to the engine for display were absolute values, not percentages, so they are being truncated. (I’m biased, of course, but to me, that sounds like a good reason to rely on a full BI solution, rather than the Google Chart API… )
The real big cause for concern is that it was apparently only when the webmasters read Seth’s blog posting that they realized they had a problem…