Where, under any provision of these regulations, interest is required to be paid at the standard rate, the interest is calculated in accordance with this Regulation.

During any financial year F1which ends on or before 31st March 2011 the rate of interest is ((RI-RE)/RE x 100)+3.5 % per year, where—

• RI is the retail prices index for September in the previous financial year, and

• RE is the retail prices index for September in the financial year before the one referred to in the definition of RI

From 1st April 2011, the rate of interest is the Superannuation Contributions Adjusted for Past Experience discount rate set by the Treasury.

Interest is compounded with monthly rests.