I'm new to Excel 2007, and I'm having some problems with conditional formatting. I have two columns of data, N and I. Some of the cells in column I are empty/blank, and the conditional formats are in column N. For example, if I2*1.05 is greater than the value of N2, I want N2 to be boldfaced red. If I2 is empty/blank, I want the format of N2 to be unchanged. The first conditional format, "if I2*1.05 is greater than N2, then the N2 value is boldfaced red" is easy, but what is the syntax for "if I2 is empty/blank, then leave N2 formating unchanged?"

Thank you.