You're a bit off about CD's. They weren't popular yet, but they did exist. They first went on sale in the US in 1983, and 4% of albums sold in 1985 were on CD.

You're a bit off about CD's. They weren't popular yet, but they did exist. They first went on sale in the US in 1983, and 4% of albums sold in 1985 were on CD. For portable music in 1985, there were also cassette tapes.