EQ_Infographic_top-546x1024“Top 40 charts were designed for your mom,” chirps the press release for US personal radio service Slacker’s new feature: the Slacker EQ Score.

It’s a metric created by the company to reflect how popular songs are among its users, which gives every track a score between one and 100.

Factors include how many times a song was started; how many times it was listened to in its entirety; how many times people ‘heart’ it and share it; how often people change stations when the song is playing, and how many people skip and ban it from their streams.

The scores will be updated every Thursday, along with a chart of the 40 “most engaging” tracks.

“The majority of people stream music and old charting methods capture sales or basic streams which only tell a fraction of the story,” says Slacker’s Jack Isquith in a statement. “As access to music trumps ownership for consumers, engagement quickly becomes the most important metric for what’s hot and trending.”

The chart makes an interesting comparison with the recently-launched Spotify 50 chart for that service. Looking at the respective top 10s in the US for the last week, there’s some overlap: tracks by Imagine Dragons, Justin Timberlake, Icona Pop and Selena Gomez appear in both.

But some interesting differences too: Daft Punk are nowhere to be seen in Slacker’s Top 40, for example, while ‘Get Lucky’ makes two appearances in Spotify’s top 10 thanks to its radio edit and album version.

Demographic differences are one reason for this: “You’ll notice that the Country and Pop audiences are highly engaged when compared to their Rock and Alternative counterparts,” says Slacker on its EQ chart webpage.

Slacker and Spotify’s charts – the latter company has a separate ranking for the most-shared tracks on its service – are part of a wider trend for new charts to spring up trying to find the metrics to measure musical success in the digital world. Billboard’s Social 50 and the inclusion of YouTube streams in its main chart being other examples.