create table shares 
(shares number)
/

insert into shares (shares) values (10);
/
insert into shares (shares) values (50);
/
commit;
/

--message(:col_right_type_shares.total_shares);
--message(:col_right_type_shares.total_shares);
--message(:system.last_record);
DECLARE
  lv_current_record   number;
  lv_cursor_item      varchar2(61);
BEGIN
   message('wvblock.looping ' || :wvblock.looping);
   IF nvl(:wvblock.looping, 0) = 0 THEN
--    lv_current_record := get_block_property(:system.trigger_block, current_record);
  --  lv_cursor_item := :system.cursor_item;
    :wvblock.looping := 1; 
    first_record;
          LOOP
              message(:system.last_record);
              message('record # ' || get_block_property(:system.trigger_block, current_record));
              synchronize;
              IF :system.last_record = 'TRUE' THEN
                   IF :shares.shares <> 100 - :shares.total_shares THEN
                          :shares.shares := :shares.shares + 100 - :shares.total_shares;                                       
                   END IF;
              END IF;
              next_record;
              exit when :system.last_record = 'TRUE';
          END LOOP;
              --go_item(lv_cursor_item);
              --go_record(lv_current_record);
       --       message(:wvblock.looping);
      
   END IF;
   :wvblock.looping := 0;
END;    

if :shares.total_shares <= 100 then
   null;   -- i.e. don't do anything - summary item is < 100
else
   :shares.shares := :shares.shares + 100 - :shares.total_shares;
end if;