Another interesting set of numbers is the percentage of lots sold above versus below the auction houses' estimate range. Overall, the number sold above runs significantly higher. Almost twice as many books sold above the high estimate as below the low estimate. What does this mean? Was the market better than most people expected? Are book prices soaring? Not necessarily. Most auctions have minimum bids. Some have hidden minimums, also known as "reserves." And some auctions have minimum bids as high as their low estimate. Naturally, these houses won't have sales below the low estimate but they will usually have unsold lots because every lot won't attract a minimum bid. To make the comparison fair, we'll add the number of lots unsold to those sold below the low estimate and compare that to the number sold above the high estimate. After all, unsold lots are, in effect, lots that could only sell below the low estimate. When you make that comparison, a very different picture emerges.

For 2004, 27% of the lots sold below the low estimate, 49% above the high. But, include unsold lots as lots "sold" below the low, and the ratio is 45% below the low estimate, 37% above the high. Now it looks like the estimates run a bit high, or sale prices were somewhat below expectations. Here are the charts.