Question 182021
I would put "# of years (since 2009)" on the x-axis and "age (in years)" on the y-axis. Then you would have 2 parallel lines, one starting at 35 and going 36, 37, 38,... and the other starting at 46 and going 47, 48, 49,... I would probably make one of the lines dashed and one solid, and put a key on there to indicate which is which.