PROBLEM WITH FUNCTION

HI list,
i have a next function

CREATE OR REPLACE FUNCTION "public"."contador_distrito_activos" (numeric,
numeric, numeric) RETURNS SETOF "public"."ty_activo" AS'
declare
  con bigint;
  act bigint;
  emp alias for $1;
  sed alias for $2;
  zon alias for $3;
begin
  con := contador_distrito(1,2,5);
  if (con > 0) then
     act := ( select count(*) from activos where
             activos.co_empresa = 1 and
             activos.co_filial = 2 and
             activos.co_zona = 5);
     if act isnull then
        act := 0;
     end if;
  else
     con :=0;
     act :=0;
  end if;
return con , act;

end;
'LANGUAGE 'plpgsql' VOLATILE CALLED ON NULL INPUT SECURITY INVOKER;

But this function only return the value of con ;

any idea

Thank