def header(self):
        """ Show summary header. """
        # Different header for wiki: Updates on xxx: x changes of y pages
        item(
            "{0}: {1} change{2} of {3} page{4}".format(
                self.name, self.changes, "" if self.changes == 1 else "s",
                len(self.stats), "" if len(self.stats) == 1 else "s"),
            level=0, options=self.options)