In the U.S. market, the cost of using mobile voice has declined, whitle the cost of using fixed network voice has climbed since 2009, according to the U.S. Bureau of Labor Statistics, measured using the Consumer Price Index. Compared to 1997, mobile voice prices are down by about 55 percent. Since 2009, mobile voice prices dropped about 20 percent.
On the other hand, the cost of fixed network voice over that same period, measured using the CPI, has climbed. Since 2009, fixed network voice prices have climbed nearly 20 percent.