Joe Biden's Fuzzy Math: Can anyone explain what he was saying here?

Not even David Gregory was buying it today....
Listen to this foolishness in the first 30 seconds of this clip from Biden..



Biden: "No one realized how bad the economy was, the projections turned out to be worse"..

Gregory: "Package was sold on the premise it would keep unemployment at 8%"

Biden: "Everyone guessed "wrong" at the time the estimate was made about what the state of the economy was at the moment that this was passed."
Still Bush's fault....