South Australia (Australia) is 3.7 times larger than New Zealand.
Area: 267,710 km2 World Factbook
Population: 4,401,916 (July 2014) World Factbook
New Zealand is an Oceanian island country in the southwestern Pacific Ocean. The country geographically comprises two main landmasses – that of the North Island, or Te Ika-a-Māui, and the South Island, or Te Waipounamu – and numerous smaller islands. Wikipedia
South Australia is a state in the southern central part of Australia. It covers some of the most arid parts of the continent. With a total land area of 983,482 square kilometres, it is the fourth largest of Australia's states and territories. Wikipedia