"A weak currency won't necessarily lead to a crisis. But, if it makes it harder to pay for a deficit that is owed to overseas creditors, that's when it could become a problem. That's what the newly appointed governor of the RBI, the Indian central bank, Raghuram Rajan, and I discussed last year when he was the government's senior economic adviser. We talked about the risk that India could experience a repeat of the 1991 balance of payments crisis. The country ended up being rescued by the International Monetary Fund."

http://www.bbc.co.uk/news/business-23612146