Re: [gutvol-d] Addition to PG History PT1

Before December 1990, PG's collection size did not grow exponentially. Between December 1990 and August 1997, the collection size grew exponentially with a 12-month doubling time. Between August 1997 and August 2000, the collection size grew exponentially with a 27-month doubling time. Between August 2000 and December 2004, the collection size grew exponentialy with a 20-month doubling time. On average, between December 1990 and December 2004, the collection size grew exponentially with a 16-month doubling time. 1991 is a fine year to begin exponential fitting, but our present rate of exponential growth is somewhat less than it has been historically. -- RS