can't add rows to existing spreadsheet Numbers OS X Yosemite
I created a numbers spreadsheet with column filters and also popup menus for some columns I am trying to add additional rows to the spreadsheet I followed instructions from numbers:
- Add or delete a row or column at the edge of the table: Click
at the bottom or 
at the top of the table. (Drag the control to add or delete more than one row or column.) You can delete a row or column only if all of its cells are empty. - Insert or delete a row or column within the table: Click the table, move the pointer over a numbered or a lettered bar, click the arrow, then choose a command from the menu that appears.
but the options to add rows are shaded gray so you can't add rows but can add columns. the II for add columns is active but there is a double circle where the = should be at the top of the table.
I am a 20 year windows and excel user but am new to Apple and numbers
iMac (21.5-inch, Mid 2014), OS X Yosemite (10.10.1)
