The ever-inventive folks at Google have charts that show word usage over time. I tried “uncirculated” and the resulting graph parallels the growth of numismatics in the 1960s, leading up to the precious metals collapse in 1980. “Overdate” suggests an initial burst of interest in the 1930s – perhaps related to Wayte Raymond’s launch of the Standard Catalog in 1934? The great “cent” vs. “penny” debate can also be settled – while “cent” may be the legally correct term, public usage of “penny” shows an uptick while “cent” trends downward since the 1940s. A few more obscure terms gave no results – Google apparently limits these charts to terms with sufficient use for statistical purposes.