New South Wales (Australia) is 2.4 times larger than Vietnam.
Area: 331,210 km2 World Factbook
Population: 93,421,835 (July 2014) World Factbook
Vietnam, officially the Socialist Republic of Vietnam, is the easternmost country on the Indochina Peninsula in Southeast Asia. With an estimated 90.0 million inhabitants as of 2013, it is the world's 13th-most-populous country, and the eighth-most-populous Asian country. Wikipedia
New South Wales (abbreviated as NSW), is Australia's most populous state, and is located in the south-east of the country, north of Victoria, south of Queensland, east of South Australia, west of Jervis Bay Territory and encompasses the whole of the Australian Capital Territory. Wikipedia