: Well, they don't purport to be the same sale.  Mackay claims that basket was exchanged at one point.  The other price is the price listed in a catalog.  Several explanations are possible: Mackay's anecdote was simply incorrect; the price in the catalog was wishfully higher; Mackay's lower price occurred earlier in the mania when prices were somewhat lower; Mackay's price occurred for an even smaller bulb; I'm sure there are other explanations.  As for an average Viceroy price, there was a Dutch economist named N.W. Posthumus, who compiled extensive price data in the 1920s.  It's possible his work would have this information, but I don't have access to it and can't read Dutch!  Citation below, if you're interested.    

 * "Die speculatie in tulpen in de jaren 1636 en 1637." Parts 1-3. Economisch-historisch jaarboek 12 (1926): 3-19; 13 (1927): 1-85; 18 (1934): 229-40.