Death data from 1994-1998 cannot be compared to that from later years (2001-2005) because the International Classification of Disease, Revision 10 (ICD-10) began to be used in 1999 to code deaths. There is a substantial difference between ICD-10 and ICD-9 which was used previously. Also the standard population that is used to figure age-adjusted rates changed from the 1970 standard population to the 2000 standard population in 1999. Birth data can be compared across years because the birth indicators are not age-adjusted.
