Figure 7 of
Heys, Mol Vis 2004;
Figure 7. Change in accommodative power (diopters) as a function of age
Accommodative power of human subjects expressed as a function of age. The data points on the graph represent a summary of four separate studies on human accommodation as indicated by the following references. Data were taken from  for curve 1 (blue diamond), from  for curve 2 (red square), from  for curve 3 (green triangle), and from  for curve 4 (open circle). This includes the regression of a straight line as modified from Pierscionek and Weale .