here). It comes from Chapter 19 of the 2012 Global Energy Assessment by IIASA (here in PDF).
The graph shows for 10 countries the historical growth in energy access. In 1920, only 35% of Americans had energy access (here shown as "electricity access" defined as "household electrification"). This total reached 100% by the mid-1950s. In contrast, Mexico was at about 35% access in 1930, and has yet to get all the way to the 100% mark. China went from 35% in 1970 to 100% by about 2005, a very similar rate to that of the United States. You can see India is following a much shallower trajectory, going from about 25% in 1980 to 65% in 2010.
How fast can energy access occur? These data provide some insight into that question.