Daily forward rates are the optimal choice to serve as proxies for medium-term expectations when calibrating the Gauss+ model’s medium-term factor (mₜ). These rates capture real-time market sentiment about expected interest rate movements over two to three years, providing vital insight to adjust the medium-term settings accurately.

A is Incorrect. Non-financial data like temperature fails to provide meaningful interest rate inputs.
C is Incorrect. Annual data lacks the resolution needed for responsive term calibration.
D is Incorrect. Isolating transaction data without context omits broader market dynamics.

Things to Remember:

• Forward rates bridge expected movements and real-world model calibration.
• Account for timeliness and relevancy to enhance model predictability.
• Focus-appointed data improve the lot of parameter precision and market alignment.