A family of Microsoft spreadsheet software with tools for analyzing, charting, and communicating data.
In my case, it happens quite often, maybe every half hour on average, but new input data just gets lost rather than going into the wrong workbook. So as soon as I notice it's not responding, I hit enter and let it flip to some other open workbook, then reselect the one I'm working on and re-input the new data. Once I even saw it flip to another workbook when I wasn't even touching the keyboard!
Ken.