Halfpenny (Australian)

The Australian Halfpenny was a coin used in the Commonwealth of Australia prior to decimalisation. The coin was first minted in 1911 and minting ceased in 1964, excluding 1937, 1956–1958 inclusive. When the Australian currency was decimalised on 14 February 1966 the coin was equal to  ⁵⁄₁₂c.

Counting the known mintages of proofs, a total of 422,882,890 (422 million) coins of the denomination were minted during its existence.

...
Wikipedia