Between 1987 and 2007, booklet panes – unlike miniature sheets – usually show an unprinted margin caused by the stapled binding of the seal booklets. Minor size differences between miniature sheets and booklet panes result from technical production tolerances and appear to be random.
Miniature sheets were and are issued both separately and in souvenir folders. Booklet panes are identical in design but, between 1987 and 2007, show an unprinted margin strip due to the stapled binding of the seal booklets. In the years without such margins, the miniature sheets themselves fulfilled the function of booklet panes.