The art market moves in cycles with activity generally peaking in the spring and autumn when the major auction houses traditionally schedule auctions, and results in the market being seasonal rather than ongoing. While private sales take place all year, those sales are often not publicized as auctions are and thus do not affect the market until they become known. Art valuations made for an autumn auction may be unrealistic for the following spring auction season because fortunes in the financial markets during one season can affect the art market in the following season, and equity markets do significantly impact the art market. Volatility in the financial markets often causes volatility in the art market as happened in the contraction of the art market during the 2008-2009 recession when sales at Sotheby's, Christie's, and Phillips de Pury & Company were less than half the previous year: November 2008, $803.3 million compared to November 2007, $1.75 billion; and between 2000 and 2003 when the annual volume of art works sold at auction dropped 36%. In other instances, the art market can fare reasonably well despite volatility in the stock market such as happened from January 1997 through May 2004 when the average quarterly fluctuation in the Artprice Global Index was two to three times smaller than the same statistic for the Dow Jones Industrial Average and the S&P 500. As art market participants' fortunes wax and wane in the financial markets, buying power evolves and affects participants' ability to afford highly valued works, resulting in new buyers and sellers entering, leaving, or re-entering the market, and an artwork sold to offset losses in the financial market might be sold for substantially more or substantially less than its last at auction. In the late 1980s during the stock-market boom, the art market expanded in turn with prices soaring to new heights, and investment firms took a greater interest in the art market and began to study it in-depth. Concurrently, the previously non-transparent art market became more accessible via the increasing availability of indices and online data although researchers discovered biased price estimates in the auction houses. Art sometimes has transient fashionability that also can affect its value: what sells well for a time may be supplanted in the market by new styles and ideas in short order. For instance, in the spring of 2008 a collector offered over $80 million for Jeff Koons' stainless-steel "Rabbit", and yet a year later, of four works in the fall auctions at Christie's and Sotheby's in New York, only two of his pieces sold well and one failed to sell entirely.