The Paul Ryan deficit-elimination plan assumes that unemployment will drop to 2.8% by the year 2028. As Paul Krugman points out, the only time we've been at this level was briefly, during the Korean War. Even during the crazy .com, unemployment barely broke below 4%. Seriously, if Obama announced a plan with something like that, he'd be mocked left and right. And again, via Krugman, the Heritage Foundation table pointing out the number. You can see the 2.8% estimate in the very bottom right hand.