<prompt> Human: Ever since I opened my checking account, Ive kept close track of how much money I have in it. I balance my sheet every month against my monthly statements. After balancing, the statement from my bank usually has a slightly different final balance due to transactions that had not yet posted from the current month. Anywho, over the past few years Ive noticed the difference grow larger and had no idea why. After a while, I realized this amount sticks around 400. Ive been using it as sort of a buffer to prevent myself from overdrafting for a couple of years now. A few weeks ago, I called my bank to ask them how I can figure out where these funds came from, since Ive never noticed anything odd on my statements, but they were no help. They cant give me records more than a few months back without charging me. Its probably a long shot, but does anyone here have any advice or suggestions as to how to figure this out?  <response>: We had mystery money showing up in our joint account for a while. After 3 months I finally realized drunk me had set up a monthly auto-transfer and was still manually putting my share of money into the account. Ha, where is all this money coming from!?! 