Complex sentence: The album debuted at number one on the "Billboard" 200, becoming Jackson's seventh album to top the chart in the United States making her the third act in music history to have a number one album in the last four decades.
Split into simpler sentences: The album debuted at number one on the "Billboard" 200, becoming Jackson's seventh album to top the chart in the United States. This made her the third act in the history of the chart to have a number one album in each of the last four decades.