1 Jan 1976 to 31 Jan1976
US foreign surface letter rate 18 c
Swedish foreign surface letter rate 110 öre
US handstamp shows amount missing in US cents (normally double deficiency) and US surface letter rate.
In Sweden the indicated fraction multiplied by 110 rounded up to next 5 öre and a handling fee of 100 öre were normally paid by affixing stamps on the item. During January 1976 the new system with single deficiency+handling fee was used but the use of enclosed due advice cards did not start until 1 Feb 1976
Air mail postcard with 13 cent. Correct rate 21
cent. Shortpaid 8 cent. US due handstamp indicates deficiency 8 cent and
foreign letter rate 18 cent. Amount due in Sweden 8/18 of foreign letter
rate 110 öre = 48.89 öre rounded up to 50 öre and a handling
fee of 100 öre, totally 150 öre. The amount has been paid by
affixing stamps on the item.