On 1 January 1901 the six self-governing Australian colonies federated as the Commonwealth of Australia, and to this day Australia remains a federation of those six "original States" under the Commonwealth Constitution. Australia is the fifth oldest federation in the world after the United States (1789), Switzerland (1848), Canada (1867) and the German Empire (1871) and the only one of those to have remained entirely unchanged in its composition. In formal constitutional terms, little has been altered since Australians made that decision over a century ago; in practice, however, the way Australian federalism functions has changed enormously over the intervening years. The most significant respect in which it has changed is in the degree to which the Commonwealth government has assumed a position of dominance.