Despite those who would hate to see Saturday mail delivery stop, most of us probably won't mind: your postman is carrying fewer and fewer personal letters in this age of email. Today Americans on average receive only one personal letter every seven weeks, a decrease from one every two weeks back in 1987, the AP reports. An important caveat is that holiday and birthday cards are not included as personal letters. Still, this spells even more trouble for the Postal Service, which is facing big funding cuts from Congress and is running billions of dollars in the red. The decline of letter-writng is also cause for hand-wringing among historians, who use snail mail as historical documents, the AP says. Say one Cornell history professor: "Part of the reason I like being a historian is the sensory experience we have when dealing with old documents. Sometimes, when people ask me what I do, I say I read other people's mail."