There have been 65,536 rows, all numbered. That makes 16,777,216 cells. That was the case up to Excel 2003. In Excel 2007 the maximum number of rows per worksheet increased to 1,048,576 and the number of columns increased to 16,384 which is column XFD. That makes 17,179,869,184 cells. Excel 2010 and Excel 2013 have the same amount of rows and columns.