Three years later, a new set of stamps were issued.

Five will feature in a set of stamps, the company says.

A set of three stamps was issued on May 15, 1859.

The first set of five stamps was issued on 16 May 2008.

On 1 October 1993, a set of stamps was released to the general public.

A set of two stamps was released in September 1999.

One set of nine stamps on a medical theme, for example, is $135.

One set of four stamps was issued every month, and each had a common theme.

On eBay, a set of 50 stamps was selling for $200.

Portugal's Christmas issue is a set of three stamps designed by children.