After working through many, many threads on this topic, I have a solution that's close. Using your code does return a date in the cell with =LastSaved(). However, the date is way off. First it said 2011, after another save it went to 2008. I'm moving back in time, although not in a way that allows me to take advantage of the stock market.
Any idea what could be going so horribly wrong?
FWIW, I have entirely closed out of Excel between saves, the workbook is saved as xlsm, and my computer is well aware of today's date and correctly stamps the file in properties.
Thanks!