The penalty Interest Rate fixed by the Attorney General under the penalty Interest Act 1983  is 12% per annum with effect on and from 1 July 2004, to be published in the Government Gazette on Thursday 24 June 2004.

 The following taken from the Government Gazette is a list of the 
 Penalty Interest Rates under SC 2 of Penalty Interest Rates Act 1983
1 July to Current 12.00%
21 June 2003 to 30 June 2004 11.25%
24 March 2003 to 20 June 2003 11.00%
18 December 2002 to 23 March 2003 11.50%
25 August 2002 to 17 December 2002 12.00%
 4 May 2002 to 24 August 2002 12.25%
 17 April 2001 to 3 May 2002 11.50%
 23 February 1998 to 16 April 2001 12.30%
 30 October 1991 to 22 February 1998 13.20%
 1 May to 29 October 1991 15.00%
 19 December 1990 to 30 April 1991 16.10%
 12 July to 18 December 1990 18.50%
 1 February to 11 July 1990 19.60%
 1 November to 31 January 1989 23.50%
 1 July to 31 October 1989 13.70%
 1 April to 30 June 1989 13.60%
 1 January to 31 March 1989 11.90%
 1 October to 31 December 1988 11.80%
 1 July to 30 September 1988 12.50%
 7 April to 30 June 1988 12.50%
 1 April to 6 April 1988 13.20%
 1 January to 31 March 1988 13.20%
 1 October to 31 December 1987 12.30%
 1 July to 30 September 1987 12.50%
 1 April to 30 June 1987 14.00%
 1 January to 31 March 1987 13.50%
 1 October to 31 December 1986 13.90%
 1 July to 30 September 1986 13.20%
 1 April to 30 June 1986 13.80%
 1 January to 31 March 1986 15.10%
 1 October to 31 December 1985 14.10%
 10 July to 30 September 1985 14.20%
 1 April to 9 July 1985 13.50%
 1 January to 31 March 1985 13.60%
 8 October to 31 December 1984 13.70%
 1 October to 7 October 1984 14.00%
 1 July to 30 September 1984 14.00%
 1 April to 30 June 1984 14.70%
 1 January to 31 March 1984 13.30%
 1 July to 31 December 1983 15.80%