Refer to the graph. A line graph titled U S Popular vote for president as percentage of total population shows year on the x axis from 1788 to 2012 and percent on the y axis from 0 to 50 in increments of 5. In 1788, 2 percent, increases to 10 percent in 1828, 15 percent in 1868, 20 percent in 1916, 37 percent in 1940, 41 percent in 1992, 44 percent in 2008. Based on the graph, what conclusion can be drawn about the impact of the 19th Amendment?