Earlier quoted context omitted.
Sweden chose not to join the Euro. Oddly - European nations that don't use the Euro are generally much better off: Norway (though not EU), Denmark, Sweden, UK. In hindsight, the UK's decision to not join the Euro is widely accepted as smart. The Euro is effectively a 'hard Germany currency' that has entrapped the periphery of Europe into a monetary system that massively favours the Germans. Maybe it could have worked…
> Denmark The Danish Krone is pegged to the Euro, within a very tight margin. http://www.xe.com/currencycharts/?from=DKK&to=EUR&view=5Y And you've missed Poland, Hungary, Czechia, Romania and Bulgaria; these countries don't use the Euro, but aren't usually considered much better off.
But they are definitely different - they were closed economies, way behind, and there's advantages to their having the Euro (should they get it). Which is different from Greece/Spain.
Moreover, they want to be in the Euro :) the Swedes, Danes, English etc. chose to not use it.