Simplify the following text for a Grade 4 native English-speaking person.
Original: STP went on to become one of the most commercially successful rock bands of the 1990s , selling nearly 40 million records worldwide , including 17.5 million units in the United States , before their dissolution in 2003 .
Simplified: The band 's five albums have sold more than 17.5 million in the United States alone and more than 30 million albums worldwide .