Displaying multiple axis on one graph

[vlayton500]

I have a spreadsheet wich tracks and predicts future investment value over a 30 year time period and I want to display the year on the bottom axis of the graph and the persons age on the top axis. Any help woul be appreciated.

 

[Asala42]

I'm not aware of a way to get two x-axes (top and bottom), although you can get two y-axes via the "secondary axis" chart option.

Are you willing to flip the chart on it's side? It sounds like it would just be a different view of the same data. (At least that's my impression)