Simplify the following text for a Grade 8 native English-speaking person.
Original: The album was Oasis ' most enduring commercial success , charting at number one in the UK ( staying there for 10 weeks ) and number four in the U.S. .
Simplified: The album was Oasis ' highest selling album , charting at number one in the UK ( staying there for 10 weeks ) and number four in the U.S. .