diff --git a/southamerica b/southamerica
index 3c9202b..c69c869 100644
--- a/southamerica
+++ b/southamerica
@@ -350,14 +350,16 @@ Rule Brazil 1997 only - Oct 6 0:00 1:00 S
# Decree 2,495
# (1998-02-10)
Rule Brazil 1998 only - Mar 1 0:00 0 -
-# Decree 2,780 (1998-09-11)
-# adopted by the same states as before,
-# specifies only the 1998-10-11 and 1999-02-21 transitions;
+# Decree 2,780 (1998-09-11).
+# specifies only the 1998-10-11 and 1999-02-21 transitions.
+Rule Brazil 1998 only - Oct 11 0:00 1:00 S
+Rule Brazil 1999 only - Feb 21 0:00 0 -
+# Decree 3,150
+# (1999-08-23) specifies only the 1999-10-03 and 2000-02-27 transitions;
# after that, these rules are guesses and are quite possibly wrong,
# but they are more likely than no DST at all.
-Rule Brazil 1998 max - Oct Sun>=8 0:00 1:00 S
-Rule Brazil 1999 max - Feb Sun>=15 0:00 0 -
-
+Rule Brazil 1999 max - Oct Sun>=1 0:00 1:00 S
+Rule Brazil 2000 max - Feb lastSun 0:00 0 -
# Zone NAME GMTOFF RULES FORMAT [UNTIL]
#