Hello, I am trying to add conditional formatting to a worksheet using a column as a nominal tolerance and then having a formula to determine if the other cell is large or smaller the cell will turn red. For example Column A has a specification and Column B has the measured value. I would like to do conditional formatting for column B. For example Column B > (column A +0.5) and Column B < (column A -0.5) the cell should turn red. However, in the worksheet Column B and Column A are always changing. I can not get the formulas to work as the results in the rows for each column changes.