Converting Old Prices To Current Value: Finally A Tool
- by Michael Stillman
Want to see what has really happened to the value of this book? Read on.
By Michael Stillman
Figuring out the value of a book is probably the most vexing issue facing booksellers and collectors alike. Not that there is any lack of data. Books have been auctioned in the open market for over three centuries. Knowledgeable booksellers have been placing prices on them for at least that long. There is an enormous wealth of information. The problem is that many of these valuations are old. How can we use this enormous body of pricing data when the ravages of inflation and changing taste have made them seemingly meaningless?
The answer is to convert these old prices into current values. We need a scale, something akin to what the Consumer Price Index does for a loaf of bread. Such a scale could translate the price a bookseller or auction placed on that book years ago into today's dollars. It would bring those old prices up to date. Now updated prices would not necessarily establish current value. Some books will have appreciated more than others in the intervening years. Nevertheless, it would tell you on average what that old price equals today. It will tell you the value that bookseller or auction placed on your book. In a world where accurate pricing information is very hard to find, this would be a major step.
At the AE, we have been compiling an enormous database (the AE Bibliographic Database) of priced records, primarily from auctions and top booksellers of many generations. Now approaching a million strong, and growing rapidly by the day, these records give us a unique window into book pricing over the past century. Now we have sorted and selected through these reams of data to generate a scale that reflects the yearly trends in book pricing. So far, the scale takes us back to 1914, but in time it will go even farther. Once the scale was created, it became possible to apply it back to each individual record to determine what that old price means in terms of today's dollars. "Book dollars," if you will, for this scale is based not on the price of bread but on the price of books. It is, so to speak, the Consumer Price Index of books.
As we noted, not all updated prices will reflect current values because of differing rates of appreciation. However, this brings us to a second, and maybe even more important use for these updated prices. The ability to convert old prices into current values will tell you how fast a book is appreciating relative to other books, which is just a polite way of saying whether it has been a good or a poor investment. Think about that. If a book sold for $100 fifty years ago, and sold for $200 yesterday, it's been a terrible investment. Most books have far more than doubled in fifty years. But, if that book sold for the equivalent of $100 in today's "book dollars" fifty years ago, and $200 today, that is a book which is appreciating at twice the normal rate. Converting old prices to current values enables you to see which books are good investments, which are not so good. Now, if your interest in books is strictly for the pleasure they bring you, then you need read no further. If at least part of your motivation in buying books revolves around money, then please continue.
Gonnelli Auction 59 Antique prints, paintings and maps May 20th 2025
Gonnelli: Pietro Aquila, Psyche and Proserpina,1690. Starting price 140€
Gonnelli: Jacques Gamelin, Memento homo quia pulvis es et in pulverem reverteris, 1779. Starting price 300€
Gonnelli: Giorgio Ghisi, The final Judgement, 1680. Starting price 480€
Gonnelli Auction 59 Antique prints, paintings and maps May 20th 2025
Gonnelli Goya y Lucientes Francisco, Los Proverbios.1877. Starting price 1000 €
Gonnelli: Domenico Peruzzini, Long bearded old man, 1660. Starting price 2200€
Gonnelli: Enea Vico, Leda and the Swan,1542. Starting price 140€
Gonnelli Auction 59 Antique prints, paintings and maps May 20th 2025
Gonnelli: Andrea Del Sarto [school of], San Giovanni Battista, 1570. Starting price 25000€
Gonnelli: Carlo Maratta, Virgin Mary and Jesus, 1660. Starting Price 1200€
Gonnelli: Louis Brion de La Tour, Sphére de Copernic Sphere de Ptolemée / Le Systême de Ptolemée. Le Systême de Ticho-Brahe…, 1766. Starting price 180€
Gonnelli Auction 59 Antique prints, paintings and maps May 20th 2025
Gonnelli: Marc’Antonio Dal Re, Ville di Delizia o Siano Palaggi Camparecci nello Stato di Milano Divise in Sei Tomi Con espressevi le Piante…, Tomo Primo, 1726. Starting price 7000€
Gonnelli: Katsushika Hokusai, Bird on a branch, 1843. Starting price 100€
Dominic Winter, May 14: Taylor (John). All the Workes of John Taylor the Water-Poet..., 1630. £1,000-1,500
Dominic Winter, May 14: Pierpont Morgan Collection. Catalogue of the Morgan Collection of Chinese Porcelains, 1904 & 1906. £2,000-3,000
Swann, May 15: Lot 4: Helena Bochoráková-Dittrichová, Z Mého Detství Drevoryty, Prague: Obzina, 1929. First trade edition, signed by the artist. $4,000 to $6,000.
Swann, May 15: Lot 10: Nancy Cunard, Negro Anthology, with a tipped-in A.L.S. to Karl Marx's niece, 1934. First edition. $3,000 to $5,000.
Swann, May 15: Lot 14: Margaret Fuller, Woman in the Nineteenth Century, 1845. First edition. $4,000 to $6,000.
Swann, May 15: Lot 17: Lorraine Hansberry, A Raisin in the Sun, inscribed first edition, 1959. $2,000 to $3,000.
Swann, May 15: Lot 28: Margaret Hill Morris, Private Journal Kept during a Portion of the Revolutionary War, for the Amusement of a Sister, 1836. First edition. $3,000 to $4,000.
Swann, May 15: Lot 38: Anna Sewell, Black Beauty: The Autobiography of a Horse, 1877. First edition. $3,000 to $5,000.
Swann, May 15: Lot 43: Gertrude Stein, Portrait of Mabel Dodge at the Villa Curonia, signed presentation copy with photograph of Stein, 1912. First edition. $8,000 to $12,000.
Swann, May 15: Lot 48: Virginia Woolf, To the Lighthouse, first edition in the scarce dust jacket, 1927. $6,000 to $8,000.
Swann, May 15: Lot 54: Katherine Dunham, large archive of material from her attorney, 1951-53. $20,000 to $30,000.
Swann, May 15: Lot 55: Margaret Fuller Signed Autograph Letter, New York City, 1846. $3,000 to $5,000.
Swann, May 15: Lot 92: Sonia Delaunay, illus. & Tristan Tzara, Juste Present, deluxe edition with original gouache, 1961. $20,000 to $25,000.
Swann, May 15: Lot 93: Flor Garduño, The Sonnets of Shakespeare, 2006. Limited edition. $6,000 to $8,000.
Sotheby's Sell Your Fine Books & Manuscripts
Sotheby’s: The Shem Tov Bible, 1312 | A Masterpiece from the Golden Age of Spain. Sold: 6,960,000 USD
Sotheby’s: Ten Commandments Tablet, 300-800 CE | One of humanity's earliest and most enduring moral codes. Sold: 5,040,000 USD
Sotheby’s: William Blake | Songs of Innocence and of Experience. Sold: 4,320,000 USD
Sotheby’s: The Declaration of Independence | The Holt printing, the only copy in private hands. Sold: 3,360,000 USD
Sotheby's Sell Your Fine Books & Manuscripts
Sotheby’s: Thomas Taylor | The original cover art for Harry Potter and the Philosopher's Stone. Sold: 1,920,000 USD
Sotheby’s: Machiavelli | Il Principe, a previously unrecorded copy of the book where modern political thought began. Sold: 576,000 GBP
Sotheby’s: Leonardo da Vinci | Trattato della pittura, ca. 1639, a very fine pre-publication manuscript. Sold: 381,000 GBP
Sotheby’s: Henri Matisse | Jazz, Paris 1947, the complete portfolio. Sold: 312,000 EUR