The Grand Supercycle is the longest period, or wave, in the growth of a financial market as described by the Elliott wave principle, originally conceived and formulated by Ralph Nelson Elliott. Elliott speculated that a Grand Supercycle advance had started in the United States stock market in 1857 and ran to the year 1928, but acknowledged another interpretation that it may have been the third or even the fifth Grand Supercycle wave. However, these assignments have been reevaluated and clarified using larger historical financial data sets in the works of A. J. Frost and R.R. Prechter, and the start is now considered to be 1789, when stock market data began to be recorded. Like all Elliott waves, Grand Supercycle waves are subdivided into smaller generations of waves. The next smaller generation of waves are those of Supercycle degree. Modern applications of the Wave Principle also describe waves of larger degree spanning millennial periods of time. Modern application of Elliott wave theory posits that a Grand Supercycle wave five is completing in the 21st century and should be followed by a corrective price pattern of decline that will represent the largest economic recession since the 1700s. In technical analysis, Grand Supercycles and Supercycles are often compared to the Kondratiev wave, which is a cycle of 50 to 60 years, but these are in detail distinct concepts. Possible Elliott wave position of world stock markets Some Elliott wave analysts believe that a Grand Supercycle bear market in US and European stocks started in 1987. When that was proven incorrect it was later revised to be 2000 and then 2006. During 2006–2007 the Dow Jones Industrial Average reached a new all-time high, which has been interpreted by some Elliott Wave analysts as indicating that 2000–2002 was not the beginning of a Grand Supercycle bear market. However, as this new high was merely a nominal new high in US dollars, and not a new high when measured in ounces of gold other Elliott Wave analysts believe this new high to be 'phony'. Expectation of economic recession A controversial issue is whether the severe economic recession accompanying the termination of the current Grand Supercycle will take the form of either a deflationary depression or a hyperinflationary period. Robert Prechter has repeatedly stated that the collapse will take the form of a deflationary depression probably followed by hyperinflation. In an October 2006 interview, when asked to