1970 was a major high point in American popular music. The Beatles, who would break up this year, reached the full maturity of “Let It Be” and “The Long and Winding Road.” Motown was in its glory days, as were a slew of highly creative artists, including Simon & Gafunkel, Stevie Wonder, Neil Diamond, The Jackson 5, and Sly & The Family Stone. BB King gave us the timeless “The Thrill Is Gone” and James Taylor recorded the classic “Fire and Rain.”

And then, as if a single page torn from the calendar dictated a new feel, 1971 saw an abrupt mood shift. Certainly, some of the music still focused on larger issues, like Freda Payne’s “Bring the Boys Home” and Marvin Gaye’s “Mercy Mercy Me” (The Ecology).” But pop music was coming down to earth, shifting toward a more personal focus, as in Rod Stewart’s “Maggie May,” and John Denver’s “Take Me Home, Country Road.”

The wild party of late ’60s music officially ended this year. Pop music returned to its perennial emphasis on romantic love, with the huge chart success of Roberta Flack’s languorous “The First Time Ever I Saw Your Face.” The exuberance of Don McClean’s mega-smash “American Pie” stemed from the freedom of late ’60s pop, but McClean sang mournfully of “the day the music died.” Proving that music was moving away from a larger awareness, Rat Pack alumni Sammy Davis, Jr. scored a big hit with the hyper-bubbly “Candy Man.”

Sometimes an art form grows exhausted, and pop music clearly did in 1973. The runaway success of the insipid “Tie A Yellow Ribbon ‘Round the Old Oak Tree” and “Bad Bad Leroy Brown” demonstrated that the creativity of the last few years had run dry. Still, pop music had moments of genius this year, like Marvin Gaye’s inspired “Let’s Get It On,” and early hits by the Allman Brothers, Elton John, and David Bowie.

Barbara Streisand had a very big year, granoloa-fueled artist John Denver sold a mountain of singles, and the thoughtful pop of Cat Stevens proved to have staying power. After a short post-Beatles hiatus, Paul McCartney scored hits with Wings, notably “Band on the Run.” Meanwhile, the Jackson 5 and Kool & The Gang laid the foundation for ’70s funk, a genre that would produce some great art, reaching a high point with 1979′s “September” by Earth, Wind & Fire.

In the wake of some very sour national events, including Richard Nixon’s resignation and the inglorious American departure from Viet Nam (followed promptly by the collapse of a country that the US had lost 58,000 soldiers defending) the pop charts responded by getting light – really light. No one ever accused 1975 stars the Captain & Tennille of being big thinkers, but with the country this hungry for distraction, froth was in. Even the mindless “Kung Fu Fighting” was a massive hit with the national mood this dispirited. Mellow balladeers Frankie Valli and Neil Sedaka, who had been teen idols in the early ’60s, enjoyed a comeback. Pointing to the next wave, “Get Dancin’” was a minor hit for Disco Tex & The Sex-O-Lettes.

As the public’s mood stayed low, pop music offered a solution: Disco. With disco, one can turn off the mind altogether — don’t think, just dance! Climbing the charts were “Disco Lady” by Johnnie Taylor and “Boogie Fever” by the Sylvers. Also keeping things soporific were Seals & Crofts, Barry Manilow, and Hall & Oates. But as always, there were nuggets of brilliance amid the chaff, like Queen’s “Bohemian Rhapsody” and the tuneful pop of Electric Light Orchestra and Fleetwood Mac.

There’s no way around it: 1977 was a dismal year for pop music. The handful of notable exceptions include Abba’s “Dancing Queen” and Stevie Wonder’s “Sir Duke.” Overall, though, the year subsisted on white-bread conformity, as a genre of mild-mannered ’70s rock emerged, defined by Aerosmith, Heart, Kansas, and the Eagles – all talented groups with narrow ambitions. Elvis Presley, now truly a relic from another age, had a minor hit with “Way Down” before dying in a pill-induced stupor.

Disco flowered this year, and the Bee Gees (once a groovy ’60s rock band) became disco royalty – if anyone could turn disco into an art form, they could. Having less artistic success (but great commercial success) was Debbie Boone, whose mega-smash “You Light Up My Life” may have been the worst hit ever. This year’s high points included some good work from the Rolling Stones, with “Miss You,” and the pop genius of Steely Dan.

By 1979 the country was in such a bad mood – partially due to OPEC-induced runaway inflation – that Jimmy Carter addressed the nation in July 1979 to talk about the “crisis of confidence” that “strikes at the very heart of our national will.” With that much malaise – creating a great hunger for distraction – disco reached its zenith. Many radio stations went to an all-disco format, and kids carried disco-themed lunch boxes to school. The Village People released “Y.M.C.A.,” the genre’s most enduring hit.