An ultra-rare 1975 dime stashed away for decades just surfaced—and sold for a whopping $500,000

Anyone else find it slightly annoying that the main picture Fortune chose for this article is a 2005 dime?

That's about 4.38% annual return over 40 years. Not terrible, but could have done better investing in something else.

EDIT: The brother paid $18,200 for the dime. But my original number of 4.38% was off because I used the inflation adjusted $90k cost. More accurate number is 8.64%.