The following Q&A is excerpted from Clifford Mishler’s Coins: Questions & Answers
Q: Why do 50 State quarter mint error coins generally command much higher prices than do, for example, similar Bicentennial quarter errors of a quarter-century earlier?
A: In two words, popularity and presence. For starters, generally speaking, Bicentennial quarter errors of a particular type are generally available in greater numbers than are 50 State quarter errors. This is in part due to the fact that the total production of Bicentennial quarters was somewhat in excess of 800 million at both the Philadelphia and Denver mints, while 50 State quarter productions for individual states at one mint generally fell within a range of only a bit above 200 to somewhat over 400 million, with the exception of those issues from the last of 1999 (Connecticut) through the first of 2001 (New York), for which the range was from about 500 million (New Hampshire 2000-D) to nearly one billion (Virginia 2000-P). In addition, quality control at the mints was looser in the 1970s than in the first decade of the 21st century. Then, there is the matter of popularity, with the 50 State quarter series issues being subject to a greater intensity of interest than are the Bicentennial quarters.