Volume Balance Equation:
$R_{total} = (w_{post} \times R_{post}) + (w_{pre} \times R_{pre})$
At Reference Date (2026.54, Δt = 3.67y):
• $w_{post} = 1 - e^{-\ln(2) \cdot 3.67 / T_{1/2}} = 1 - e^{-0.693 \cdot 3.67 / 3.80} = 27.4\%$
• $R_{total} = (0.274 \times 35.0\%) + (0.726 \times 0.0\%) = 9.59\%$