The strength of a country's currency is good, as it will help to demonstrate more power against foreign currencies, and it's, of course, a result of a good economy. But this is not an absolute measure of a country's economy/wealth. If not, countries like Kuwait and Bahrain should be leading the world economy.

But the case is not so, and even Japan, which takes the 4th spot has its money as devalued as $1 to ¥142. At times also, the BOJ would deliberately devalue the Yen. This measure has helped Japan sell more in the world market and hence boost its trade balance.