2004 (MMIV) was a leap year starting on Thursday of the Gregorian calendar, the 2004th year of the Common Era (CE) and Anno Domini (AD) designations, the 4th year of the 3rd millennium and the 21st century, and the 5th year of the 2000s decade.

2003 (MMIII) was a common year starting on Wednesday of the Gregorian calendar, the 2003rd year of the Common Era (CE) and Anno Domini (AD) designations, the 3rd year of the 3rd millennium and the 21st century, and the 4th year of the 2000s decade.