SCI Stable Currency Index

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Technical Matters

    Technical Matters

SCI Calculation Formulas

To determine how the SCI has performed in terms of another currency:

  1. Decide which currency you will use to measure the SCI’s performance. We’ll call this our “base” currency.
  2. Express the SCI in base currency terms using this formula:


BC = Base currency

SCIbc = SCI in BC terms (caution: quote conventions vary by currency, i.e., some currencies are traditionally quoted as native currency units per US dollar, and others are quoted in the reverse. Research carefully before completing this step.)

(t) = today

(y) = yesterday

SCIbc (Day 1) = 1.0  That is, the starting value of both the BC and the SCIbc is 1.0.

In this application, the value of the BC does not change over time. Rather, it is the currency by which you measure the SCI that does change.

Day 1 = Any starting date, e.g., 1 January 1988 or 1 January 1971

All currencies are expressed in terms of the base currency:

SGD = Singapore dollar expressed in BC terms

CHF = Swiss franc expressed in BC terms

NZD = New Zealand dollar expressed in BC terms

USD = US dollar expressed in BC terms

If you have questions, direct them to


Stable Currency Index