fix off-by-one error (closes #21330)
diff --git a/Doc/howto/unicode.rst b/Doc/howto/unicode.rst
index 87badf3..632e525 100644
--- a/Doc/howto/unicode.rst
+++ b/Doc/howto/unicode.rst
@@ -49,7 +49,7 @@
255 characters aren't very many. For example, you can't fit both the accented
characters used in Western Europe and the Cyrillic alphabet used for Russian
-into the 128--255 range because there are more than 127 such characters.
+into the 128--255 range because there are more than 128 such characters.
You could write files using different codes (all your Russian files in a coding
system called KOI8, all your French files in a different coding system called