One of the common things that I’ve noticed since I’ve started following government economic data is that the preliminary data comes in better than the final data.

When you compare month to month, you are comparing preliminary data to the prior month’s final data, so the delta, which is what the press covers, looks much better than what it is in reality.

Well, Dean Baker just caught a doozy on October industrial production data.

In bullet points:

• September hurricanes artificially depressed that month’s stats.
• September data was then revised down.
• October preliminary data, which showed a “rise” is flat when comparing preliminary to preliminary.
• If you look at just manufacturing data, which strips out the noisier utility and mining segments, that number is down from September manufacturing data.