Occasionally, 16th-century editions similar to Caxton's books appear among antiquarian book dealers and auctions, often fetching very high prices. The last Shakespeare First Folio of 1623 (first edition of the collected works of William Shakespeare) garnered a record-breaking 5.5 million in 2006. Later 17th-century folios of William Shakespeare's works can still fetch about the price of a small house but are more readily available and relatively obtainable, whereas almost all extant copies of the First Folio are owned by libraries, museums or universities and thus are unlikely to appear on the market. For the antiquarian collector, how a particular book's production fits into a larger historical context can be as important as the edition, even if it may not be a first edition.