ca April 1888 to 31 Dec 1891
US foreign surface letter rate 5 c
US Conversion rate 1 US cent = 5 goldcentimes
Swedish conversion rate 1 goldcentime = 0.80 öre for letters, 1 goldcentime=1 öre for postcards and printed matters
US marking shows the amount missing in goldcentimes.
In Sweden the indicated amount was doubled and multiplied by 0.80 for letters and 1 for postcards and printed matters. The amount due was paid by affixing postage due stamps.
Double rate letter with 5 cent. Correct rate 10 cent. Shortpaid 5 cent. US due markings indicate number of rates (2) and amount missing; 5x5=25 centimes. In Sweden the amount have been doubled and multiplied by 0.8 (2x25x0.8) and 40 has been indicated in blue manuscript. 40 öre in postage due stamps have been affixed on back.