Thank you for that great formula Sauralf! I started exploring when I saw this article; http://arstechnica.com/security/2015...ck-you-anyway/ this is interesting on several different levels; the formula,the math, as a tool. Whenever I see this sort of thing I create a spreadsheet with the formulas and lots of sample data and notes,AND the URLs and ancillary articles that led me to, then save that forever. You are immortalized on my systems, my network, my cloud, Google Drive, Dropbox, etc. Thanks again!