According to the U.S. Bureau of Labor Statistics, prices for wireless telephone services were 53.41% higher in 2000 versus 2017.
Cell service experienced an average inflation rate of -2.49% per year between 2000 and 2017. In other words, cell service costing $50 in the year 2000 would cost $32.59 in 2017 for an equivalent purchase.
Pricing changed by -11.78% in 2000, significantly below the yearly average change for cell service during the 2000-2017 time period. Compared to overall inflation for all items in 2000 (3.27%), price inflation for cell service was much lower.
Raw Consumer Price Index data from U.S. Bureau of Labor Statistics for Wireless telephone services: