Katy Perry scores fourth UK number one single with 'Roar'

Katy Perry has scored her fourth UK number one single with 'Roar'.
The singer's first track from her upcoming album Prism is the third-fastest selling single of the year so far, and Perry's fastest-shifting ever in the UK.
'Roar' has sold 179,500 copies, which is only behind Robin Thicke's 'Blurred Lines' and Avicii's 'Wake Me Up' in terms of first-week sales.
Ellie Goulding slips one place to two with 'Burn' after three weeks at the top. Avicii slips one to three, followed by Klangkarussell's 'Sonnentanz (Sun Don't Shine)' and the Cedric Gervais remix of Lana Del Rey's 'Summertime Sadness'.
Drake climbs three places to six with 'Hold On We're Going Home', and Miley Cyrus drops two to seven with 'We Can't Stop'.
Lady Gaga falls one spot to eight with 'Applause'. Rizzle Kicks slips three to nine with 'Lost Generation', while DJ Fresh and Diplo drop two to ten with 'Earthquake'.
You Me At Six achieve their highest-charting single so far with 'Lived A Lie' at 11. Neon Jungle land one spot behind at 12 with 'Trouble'.
London Grammar earn their second Top 40 placing at 17 with 'Strong'.
Beyoncé leaps 43 places to 23 with 'Listen', following Sam Bailey's performance of it on last week's The X Factor. Arctic Monkeys climb back up 12 spots to 24 with 'Do I Wanna Know?'.
Olly Murs claims his tenth Top 40 hit at 35 with 'Right Place Right Time', climbing six places.
Starship re-enter the Top 40 at 39 with 'Nothing's Gonna Stop Us Now', after its use in a TV advert.
Mutya Keisha Siobhan land outside the main 40 at 50 with debut single 'Flatline', following its late release on Friday.
Source: Official Charts Company
The 1975 score debut UK number one album