In 2010, Kesha clocked the first Hot 100 leader of the decade, "TiK ToK." Plus, remembering chart feats by LeAnn Rimes, the Beatles & the Monkees.

Your weekly recap celebrating significant milestones from more than seven decades of Billboard chart history.

Dec. 28, 1996

Then-14-year-old LeAnn Rimes roared to No. 1 on Hot Country Songs with "One Way Ticket (Because I Can)," her first (and, so far, only) leader on the list.

Dec. 29, 2007

Eight years ago today, Colbie Caillat was celebrating New Year's with "Bubbly": her debut hit was amid a 13-week command on Adult Pop Songs.

Dec. 30, 1967

Before Adele's "Hello," the Beatles had their own similar classic: on this date 48 years ago, they tallied their 15th Billboard Hot 100 No. 1 with "Hello Goodbye."

Dec. 31, 1966

Less than two months after notching their first Billboard Hot 100 No. 1 with "Last Train to Clarksville, the Monkees climbed to the top again with the Neil Diamond-penned classic "I'm a Believer."

Jan. 1

Happy New Year! From U2 to you.

Jan. 2, 2010

With her first single, Kesha (then billed as Ke$ha) scored her first Billboard Hot 100 No. 1 – and the first No. 1 of the 2010s – with her breakthrough smash "TiK ToK."

Jan. 3, 1976

The Bay City Rollers skated to No. 1 on the Billboard Hot 100 with their debut chart entry, the bubblegum pop/dance hit "Saturday Night." Despite their name, they weren't from Bay City, Michigan, but Edinburgh, Scotland. They got their name by throwing a dart at a map of the U.S., which landed guess where …