BOT計畫透過財務報表內生比率修正折現率對財務效益之影響評估

Effect of Discount Rate Adjusted by the Endogenous Growth Ratio in a Financial Statement on BOT Financial Evaluation

蘇松吉(Sung-Chi Su)

指導教授 ： 李命志

共同指導教授 ： 鄭婉秀(Wan-Hsiu Cheng)

淡江大學/商管學院/財務金融學系博士班/博士(2018年)

https://doi.org/10.6846/TKU.2018.00932

摘要

由於採民間參與公共建設(BOT)模式推動之重大公共建設通常具有資金需求大、特許年限長等特性，而傳統財務評估模式之基本假設及財務參數，往往與現實環境存在諸多差異，其中以折現率或加權平均資金成本設定為固定之假設，對BOT計畫財務效益評估之影響最為顯著，很可能造成財務評估效益之扭曲，進而衍生政府與民間對財務評估結果之爭議。
本研究旨在構建BOT計畫透過預計財務報表內生比率來修正折現對財務效益之影響評估模型，藉由逐期修正變動折現率，折現計畫現金流量來評估計畫之財務效益。經由上述修正後變動折現率重新計算模擬個案之計畫自償率顯示，臺灣南北高速鐵路計畫自償率約為56.17%，國立海洋生物博物館計畫約為172.02%，均與模擬個案公司原採用固定折現率評估之計畫自償率差異頗大。
經本研究實證結果顯示，透過財務報表內生比率修正為變動折現率來評估計畫現金流量，較傳統固定折現率之評估結果更能反映計畫自償能力之準確性，變動折現率除可消除折現率估計差異外，將使計畫財務效益評估結果更具解釋及預測能力，本研究方法可適用於BOT計畫之實務操作，以及企業評價領域之延伸應用。

關鍵字

民間參與公共建設 ； 加權平均資金成本 ； 變動折現率 ； 自償率

並列摘要

Major public infrastructure projects adopting the build–operate–transfer (BOT) model generally exhibit characteristics such as a large capital and long concession periods. The basic assumptions and financial parameters in conventional financial evaluation models have frequently deviated from reality. In particular, the assumption of a fixed discount rate or the weighted average cost of capital exhibits the most significant effects on financial evaluations for BOT projects. Consequently, this practice may distort the evaluated financial performance, resulting in financial disputes between government agencies and private entities.
This study constructs an evaluation model that elucidates the effect of the discount rate adjusted by the endogenous growth ratio in a projected financial statement on BOT financial performance. The project cash flow evaluated by the periodically adjusted discount rate is used to evaluate the financial performance of a BOT project. Using the aforementioned variable discount rate, the case study reveals that the revised self-liquidation ratios for the Taiwan High Speed Rail Corporation and the National Museum of Marine Biology and Aquarium are approximately 56.17% and 172.02%, respectively. Notably, both figures differ substantially from the self-liquidation ratios estimated by the original evaluations using fixed discount rates.
The empirical results in this study demonstrate that the variable discount rate adjusted by the endogenous growth ratio in a financial statement assesses the cash flow of the project or the self-liquidation capabilities of a project more accurately than does the conventional fixed discount rate. Variable discount rate not only eliminates difference in discount rate estimation, but also exhibits stronger explanatory and predictive power on financial evaluations than does fixed discount rate. The research methodology in this study is suitable for practical operation in BOT projects and extension of the field in enterprise evaluation.

並列關鍵字

Build-Operate-Transfer(BOT) ； Weighted Average Cost of Capital(WACC) ； Variable discount rate ； Self- Liquidation Ratio(SLR)

參考文獻

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