儘管許多文獻探討權益資金成本並非是一個固定值，以及加權平均資金成本對於公司投資而言相當重要，但是卻鮮少有文獻探討如何去對會隨時間變動的加權平均資金成本進行建模。在本文中，我們提出了一個能在實證中使用的模型，且利用此模型去計算動態的權益資金成本，並且我們提出了如何使用公司層級的資料去建構模型，在本文的研究中，我們最終利用圖表表示出了動態加權平均資金成本與靜態加權平均資金成本間的差異，並且我們還提出了一個能夠在起初時點就能預測未來加權平均資金成本走勢的模型。

While many literature suggest that the cost of equity is not constant, and the weighted average cost of capital (WACC) matters for corporate investment. Few studies investigate on construct the model of time-varying WACC. In this paper, we provide the model in empirical to compute the dynamic WACC and the forecast dynamic WACC. The model focus on how to compute the cost of equity dynamics, which is the more complex part in the WACC. We show the dynamic WACC constructed by our model using some firm’s data. We show the difference of constant WACC and dynamic WACC in the empirical result by figure.

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