Dropping it where? Which column?Wow!!!! I think that was it. I tried dropping the A term portion of the formula entirely in my spreadsheet, making the formula just adc*B_TERM+C_TERM and got all the display readings to within a few tenths. I can't believe I found it. This is crazy. And all cause a few parentheses were in the wrong place. I still don't feel confident about which way the syntax should look to make it work, but I think I found the root of the problem.