If images made noise
this one would sound
Electronics almost universally become cheaper over time. But with essentially a monopoly on graphing calculator usage in classrooms, Texas Instruments can charge a premium. Texas Instruments accounted for 93 percent of the U.S. graphing calculator sales from July 2013-June 2014. Casio took the other 7 percent, according to NPD data. During that period 1.6 million graphing calculators were sold, a decrease from sales of 1.67 million during July 2011-June 2012.