It's 15 years since J-Lo strutted her way to a second UK Number 1 single - see what else was in the chart that week.

35 years ago this week, Barbara Dickson and Elaine Paige were top of the charts with their showstopping duet. See what else was in the UK Top 40 that week.

It's 20 years since London-born Gabrielle scored her long-awaited second Number 1 single.

It's 15 years since Ciara launched her career with global Number 1 Goodies.

Cassette sales are up to their highest in 15 years.

It's ten years since the Christmas Number 1 race got political with a campaign to block The X Factor from topping the chart.

Mariah's festive staple was beaten to Number 1 by East 17 25 years ago this week. See what else was in the Top 100 this week in 1994.

A sequel to one of the biggest singles ever – plus a Top 40 including Ice T, Green Day, Natasha Bedingfield, and… Nadia from Big Brother.

16 years ago, Busted and Britney went head to head for the Number 1. See what was in the chart in 2003, including Outkast, Blazin' Squad, Sugababes, and Holly Valance.

It's 20 years since the battle of the solo Spice Girls!

Look back at the Top 40 from this week in 2009, including Whitney Houston, Alexandra Burke and Alphabeat.

Key change! The Irish quintet's signature ballad hit Number 1 in 1999.

Christina's synthy, suggestive debut single ruled the UK singles chart 20 years ago.