SORA is computed based on reporting banks' concluded arms-length transactions subject to data sufficiency conditions being met.
If there are insufficient transactions on a given day, SORA will be produced using contingent data sources, as outlined below.
Conditions for data sufficiency (all conditions to be met):
- Minimum number of reporting banks: 5
- Minimum number of transactions: 10
- Minimum volume of transactions: S$500m
If any one of the above conditions is not met, SORA will not be computed using the normal calculation methodology, and a contingency process will be triggered (Contingency SORA).
The rate for Contingency SORA will be computed by first calculating the difference between the reference rate of MAS’ Standing Facility (SF reference rate) on trade date and that of the previous business day. This spread will then be applied to the previous business day’s SORA to get the Contingency SORA, subject to a floor of zero. In the event that the contingency production process is used, this will be clearly indicated under “SORA Calculation Method” on the MAS website.
Example: On day T, data sufficiency conditions are not met. Contingency SORA will be computed and published at 9am on day T+1.
Contingency SORA for day T = SORA on day T-1 + (SF reference rate on day T – SF reference rate on day T-1)
Assuming SORA on day T-1 = 0.7%
SF reference rate on day T-1 = 0.4%
SF reference rate on day T = 0.6%
Contingency SORA for day T = 0.7 + (0.6 - 0.4) = 0.9%
Assuming SORA on day T-1 = 0.2%
SF reference rate on day T-1 = 0.3%
SF reference rate on day T = 0.0%
Contingency SORA for day T = 0.2 + (0 - 0.3) = 0% (floored at zero)