學理上，海運公司每年獲利及市場的運價指數如不定期的波羅地海運價指數及定期的漢堡運價指數與供給和需求有密切的關係。本研究提出一創新方法論，3S法，即「模擬、簡化及分離」。其中，模擬係由供給與運價指數推導出模擬需求或需求與運價指數產生模擬供給;簡化則是合併供給與需求，求得連續時間上的市場變動調整因子;分離將可客觀地評估海運公司每年相對獲利。資料來源為2000年至2010年的真實數據，經驗證，發現不定期海運的兩調整因子具有一致性;而不定期海運與定期海運之每年獲利分別符合其市場特性。 In theory, shipping company’s profits and freight index, like the tramp BDI and linear Hamburg index, are closely related to supply and demand. In this thesis, a novel method namely 3S method, including simulation, simplification, and separation, is developed to evaluate the relative profits of shipping company. In the stage of simulation, the simulated demand is yielded from supply and freight index while simulated supply is obtained from demand and freight index. As for the simplification stage, the market variation adjust factor of the continuous period is received by a combination of supply and demand. Finally the separation stage can evaluate the annual relative profit of the shipping company objectively. All real data are from the literature in the years of 2000 to 2010. Two adjust factors of tramp, AFSi and AFDi, show the consistence through validation. Yearly profits of the tramp and liner are coincided with the feature of the shipping market.