Sweden wasn't in the ERM is memory serves though the central bank up there, like other Scandianvian countries, had the kroner pegged to a currency backet heavily weighted in DM.

Typically, you want your currency hedged as a function of your trading relationships, just like a company hedges it's foreign subsidiary cash flows, and that's, in grossly oversimplfied terms, how a central bank does it at the macro level.

I think Sweden, less than Finland but all the same quite significantly, was hit hard by the collapse of economic activity in the former Soviet Union in the early 1990's.

The Hun is always either at your throat or at your feet. Winston Churchill