Minor fix in manual

doc/org.texi

@@ -4770,7 +4770,7 @@ CLOSED       @r{When was this entry closed?}
 TIMESTAMP    @r{The first keyword-less timestamp in the entry.}
 TIMESTAMP_IA @r{The first inactive timestamp in the entry.}
 CLOCKSUM     @r{The sum of CLOCK intervals in the subtree.  @code{org-clock-sum}}
-             @r{must be run first to compute the values.}
+             @r{must be run first to compute the values in the current buffer.}
 BLOCKED      @r{"t" if task is currently blocked by children or siblings}
 ITEM         @r{The content of the entry.}
 FILE         @r{The filename the entry is located in.}