The monthly mean minimum and maximum temperatures over the year in Stockholm, Sweden. Show the average temperatures in Stockholm in Celsius Â» Data from nearest weather station: Stockholm, Sweden (0.0 Miles).
The postal service started the use of postal zones for large cities in 1943. By the early 1960s a more general system was needed. On July 1, 1963, ZIP codes were created for the whole country but they were not mandatory. In 1967, these were made mandatory for many types of mail. The system was soon used for all mail.
Full Answer. The United States Postal Service began using two-digit area codes in 1943 in order to define postal zones in larger cities. Beginning in 1967, the ZIP code became progressively mandatory. The word ZIP comes from the acronym for Zone Improvement Plan.. The original ZIP code was composed of 5 digits.