/added 18 Dec 2005
Postage due items from USA to Sweden
20 Jan 1950 to 31 Oct 1953
US foreign surface letter rate 5 c
US Conversion rate 1 US cent = 5 goldcentimes (during 1949 the US conversion rate changed to 3 goldcentimes)
Swedish conversion rate 1 goldcentime = 1.7 öre
US handstamp shows amount to pay in goldcentimes, normally double deficiency.
In Sweden the indicated amount was multiplied by 1.7 rounded up to nearest 5 öre and marked on the item. The amount due was normally paid by affixing stamps on the item.

Air mail letter with 5 cent. Correct rate 15 cent. Shortpaid 10 cent. US due handstamp shows double deficiency 2x10x3=60 centimes. Amount due in Sweden 60x1.7=102 öre rounded up to 105 öre. The amount has been paid by affixing postage stamps on the item.