Last year was the year of streaming, especially when it comes to music. According to Nielsen's recently released year-in-review Music report, digital streaming services grew a huge amount, taking some of the steam away from digital music sales.

Streaming Picks Up Across the Spectrum

In 2014, according to Nielsen's figures, there were 164.5 billion songs streamed through digital subscription services such as Spotify, Last.FM, Pandora, and the now-defunct Rdio.

In 2015, that figure nearly doubled to 317.2 billion streams.

The increase in streaming music, undoubtedly helped by Apple's long-anticipated introduction of Apple Music, translates into the album equivalent of 211.5 million streams, which is nearly 93 percent higher than in 2014's 109.7 million (Nielsen uses a conservative 1,500 streams-to-1 album conversion rate).

Measured against the total music industry volume, streaming music comprised 38.5 percent in 2015, up from 23 percent the previous year.

It appears that streaming is making its way to all demographics, since the week ending on Dec. 24th, Christmas Eve, set the all-time weekly record for the highest-streaming week, with nearly 7.5 billion on-demand streams. That's lot of moms, dads, and grandparents using a streaming service to fill the air with Christmas ambiance.

Digital Sales Drop

As streaming music grew, buying albums and songs through digital stores continued to shrink, though the former not as badly as the latter.

In 2015, Nielsen found, sales of digital tracks dropped by 12.5 percent, declining from 2014's 1.1 billion songs sold in 2014 to 964.8 million last year. Digital album sales declined as well, but only by about three percent, from 106.5 million in 2014 to 103.3 million in 2015.

The decline in digital music purchases at least correlates with the increase in use of music streaming services, which Nielsen takes to include not just paid services like Spotify and Apple Music, but also free-to-use multipurpose sites like YouTube and Vevo, as well as free radio streaming apps like Pandora and Slacker.

Streaming Songs, Buying Albums

Over the year, streaming music services were primarily used for listening to old favorites and random tracks from yesteryear, which Nielsen found by measuring the release date of streamed songs. Songs that were over 18 months old accounted for nearly 70 percent of all streaming volume in 2015.

But when it comes to listening to a new album from your favorite artist, streaming services was less of a dominant, industry-cannibalizing force, evidenced by the only-slight drop in digital album purchases, and the fact that album sales overall declined less steeply than in 2014.

In 2015, album sales in general dropped by six percent, which is an improvement over the prior 11 percent drop in 2014, and -- perhaps surprisingly, perhaps not -- vinyl made a comeback in 2015.

According to Nielsen, the epitome of non-digital album sales grew by 30 percent. On top of that, purchases of vinyl records accounted for nearly nine percent of all non-digital album sales.

It appears those going the old-fashioned non-digital route to purchase albums are increasingly deciding to go all the way. Are Victrolas headed for a comeback next?

The Old Fashioned Way Survives

Another oldie-but-goodie in music, the radio, continues to dominate the vast majority of music discovery. And seeing it live is making a comeback with young people.

While online streaming services and social media each now account for about a quarter of the ways people discover new music, AM, FM, and satellite radio is -- by far -- the way most people find new music, and its growing.

Nielsen found that people give credit to the radio, terrestrial or otherwise, for 61 percent of the first time they heard a new song in 2015, up from a still-dominant 57 percent in 2014. Word of mouth from friends and family took second place at 45 percent.

One last credit to the old fashioned way of listening to music. While Nielsen found that 75 percent of Americans listen to music online in a given week, the report also found that Millennials are particularly fond of live music, compared to teens and the average.

A total of 64 percent of Millennials' spending on music goes to live shows, be it music concerts, festivals, an event feature a live DJ, or a small music performance at the end of the street.

For more fascinating details on how Americans are finding, listening, and buying music, check out Nielsen's full report here.