Complex sentence: The Fair celebrated its sesquicentennial in 2004 when it set an attendance record with 1,053,978 visitors, a number topped in 2008 with 1,109,150 fairgoers.
Split into simpler sentences: The Fair celebrated its sesquicentennial in 2004, setting an attendance record with 1,053,978 visitors. That number was topped in 2008 with 1,109,150 fairgoers.