automatically changing associated cell

I have a spreadsheet with mnemonics that update on a monthly basis. I would like to create a table that collects the most recent data point from each series. If I do a static =A15 type of command I would have to manually change it every month to =A16, =A17, etc. Is there a command to make a cell equal to the last row with information on a given column? Thanks a lot, everyone.

I don't think a file would be much clearer. I want the cell B4 for example to go to the last cell in column A with data in it. That way, if column A gets updated with more data, cell B4 will reflect the most recent data point.