1 Jan 1967 to 30 April 1967
US foreign surface letter rate 11 c
Swedish foreign surface letter rate 70 öre
US handstamp shows amount to pay in US cents (normally double deficiency) and US surface letter rate.
In Sweden the indicated fraction multiplied by 70 and rounded up to nearest 5 öre was normally paid by affixing stamps on the item.
Unfranked letter. Correct rate 11 cent. Shortpaid 6 cent. US due handstamp indicates double deficiency 2x6=12 cent and foreign surface letter rate 11 cent. Amount due in Sweden is 12/11 of foreign surface letter rate 70 öre = 76.36 öre rounded up to 80 öre. Postage stamps for the amount due should have been affixed on the item, but here the amount had probably been paid in another way.