Spotify monthly active users

As Spotify accumulated monthly active users between 2015 and 2023, the American secondhand and thrift store market grew at an almost identical pace, achieving a correlation of 0.9735. The obvious implication is that streaming music is the gateway drug to buying someone else's old corduroys. Cultural anthropologists have not formally endorsed this theory, but they have not formally ruled it out, and several of them dress like they shop at thrift stores while listening to Spotify.

Spotify's monthly active users grew from around 75 million in 2015 to over 550 million by 2023, driven by global expansion, podcast integration, and the maturation of music streaming as the dominant consumption format. The US secondhand market grew from roughly $20 billion to over $40 billion over the same period, propelled by ThredUp, Poshmark, Depop, and shifting millennial and Gen Z attitudes toward sustainability and value. Both trends are expressions of the same demographic cohort — younger consumers who adopted subscription and platform models for both entertainment and commerce, and who index strongly for both streaming and resale culture. They are growing together because they share a customer.

Cohort effects are particularly treacherous in correlation analysis: when the same generation adopts multiple new behaviors simultaneously, everything that generation touches will correlate with everything else it touches. The data is not wrong; it is just describing a generation.