Simplify the following text for a Grade 4 native English-speaking person.
Original: The IPCC published its first assessment report in 1990 , a supplementary report in 1992 , a second assessment report ( SAR ) in 1995 , and a third assessment report ( TAR ) in 2001 .
Simplified: The first IPCC report was published in 1990 . More was added to that report in 1992 .