The music industry is showing its best surge in revenue in nearly two decades, led by a major shift toward streaming subscription services by Apple, Spotify and others firms, according to a new mid-year report the RIAA released this week. The report shows an 8.1 percent gain in retail revenue to $3.4 billion during the first half of 2016, the strongest growth since the late 1990s, according to report author Joshua Friedlander, SVP of strategic data analysis at RIAA. Huge gains in streaming revenue and market share fueled the increase.