Well, if you buy N of these global forever stamps, the cost will just get cheaper over time (inflation).
Since the non-postcrossing Global Forevers are circular and a bit annoying, I use 2 Forever stamps plus a 20¢ stamp (6¢ wasted - i suppose i could switch to 15¢ stamps...).
> if you buy N of these global forever stamps, the cost will just get cheaper over time (inflation).
Not if you buy them today to use later I would think. Since you gave up the $$$ today, it won’t do anything for you anymore even if you don’t buy another stamp again I’d think. Compared to buying a stamp whenever you need one in the future but not tying your cash up until that moment.
Really depends if you would be otherwise investing that money in a way that beats stamp prices. Stamp prices very consistently outpace inflation.
Over the past 5 years, they've beaten:
* VT stock (total world index fund)
* US I-Bonds (inflation-indexed bonds)
* Fed rate for T-Bills / any HYSA
* Any other bonds