Have you ever mailed a letter or package using nondenominated postage? Did you watch the clerk grab a chart to determine how much postage has been paid? Here is a pdf file of the chart the clerks use. I have found it useful myself. You download the chart at http://pe.usps.com/search/jsp/searc...dtype=2#hit0
A well regulated Militia, being necessary to the security of a free State, the right of the people to keep and bear Arms, shall not be infringed. (The exact & entire wording of the 2nd Amendment to the U.S. Constitution)
I've brought in my own chart copied from an outside website. When I've put a lot of postage on a piece, especially a parcel, I keep track of how much postage is in an area, and the clerk can check my math. Since a lot of the clerks know me, some will dispense with the counting and calculating and take my word for it.
Thanks for this site also, 22crows. Every site such as this can only add to the enjoyment of research of stamp collecting. Many (such as this one) I download if possible so I have access to it even when I'm not online.