Varying bond rate

Do you intend to use the 10yr or 1yr govt bond rate to set the rate of return? What arrangements are planned to incorporate the fluctuations in these rates that occur: over the last 40yrs the 10yr rate has fluctuated between 18% and 2%? Can you guarantee those arrangements will match the current rate rather than reflecting last year's rate? I note that up till mid year Govt was still using 8% for one of its capital return rates.