The COUNTIFS() function was new in Excel 2007.
Definition. This function counts the number of cells in a range meeting several criteria.
criteria_range1 (required). The range in which to evaluate the associated criteria. The cells in the range have to be cell names, cell arrays, or references to cells containing numbers. Empty cells and text values are ignored.
criteria1 (required). The criteria in the form of numbers, expressions, cell references, or text that define which cells will be counted.
criteria_range2 (optional). One to 127 ranges in which the criteria has to be evaluated. The cells in the ranges have to be cell names, cell arrays, or references ...