@end smallexample
@noindent
-and your diary will show
+and the fancy diary will show
@smallexample
Ruth & Ed's anniversary
@end smallexample
@end smallexample
@noindent
-causes your diary to show
+causes the fancy diary to show
@smallexample
Rake leaves
@end smallexample
@noindent
-on October 22, November 22, and December 22 of any year.
+on October 22, November 22, and December 22 of every year.
+
+@findex diary-float
+ The function @code{diary-float} allows you to describe diary entries
+that apply to dates like the third Friday of November, or the last
+Tuesday in April. The parameters are the @var{month}, @var{dayname},
+and an index @var{n}. The entry appears on the @var{n}th @var{dayname}
+of @var{month}, where @var{dayname}=0 means Sunday, 1 means Monday, and
+so on. If @var{n} is negative it counts backward from the end of
+@var{month}. The value of @var{month} can be a list of months, a single
+month, or @code{t} to specify all months. You can also use an optional
+parameter @var{day} to specify the @var{n}th @var{dayname} of
+@var{month} on or after/before @var{day}; the value of @{day} defaults
+to 1 if @var{n} is positive and to the last day of @var{month} if
+@var{n} is negative. For example,
+
+@smallexample
+%%(diary-float t 1 -1) Pay rent
+@end smallexample
+
+@noindent
+causes the fancy diary to show
+
+@smallexample
+Pay rent
+@end smallexample
+
+@noindent
+on the last Monday of every month.
The generality of sexp diary entries lets you specify any diary entry
that you can describe algorithmically. A sexp diary entry contains an