Have your customers or managers ever asked you how much their databases grew during the past year? Have you needed to plan how much disk capacity you'll need for the next year based on your database's average growth rate during the past 12 months? How long will your existing unallocated disk space last based on your current growth rate? To answer these kinds of database-growth questions or similar disk-space questions, you need some historical space-usage information about your databases. I've d...