Welcome to Hit Parade, a podcast of Pop Chart History from Slate magazine, about the hits from

coast to coast. I'm Chris Malanfi,

Chart analyst, pop critic, and writer of Slate's

Why Is This Song Number One series.

On today's show,

Among the most pivotal years for popular music is 1991, famously called

The Year Punk Broke, the unofficial kickoff of Alternative Nation.

The year R.E. M. became a chart-topping band.

Lala Palusa reinvented the festival concert for generations X and Y.

And when Nirvana ushered in the Grunge era.

Come as you are, as you were, as I want you to be. But for

the followers of the pop charts, 1991 is pivotal for an entirely different reason and rock alternative or otherwise

had little to do with it.

Spinderella cut it up one time.

1991 was the year Billboard magazine changed the way it calculated America's flagship pop charts.

A then new barcode scanning technology called SoundScan made the charts a lot more accurate and it changed our understanding of how

hit-making works not just the speed with which hits rose and fell but the hits themselves.

The years 1991, NWA back on the streets,

taking out all you commercialized suckers, we on this laid back track and we doing this

one kind of smooth so what you gonna do Drake kick it and so on let the beat

for one as we chronicled in our death jams episode of hit parade,

rap had been on the come up on the charts for all of the 1980s

...