개성상인 복식부기 장부 20세기 전후 재고자산회계

The Korea’s Registered Cultural Heritage No. 587, the Park Young-jin Family’s Double-Entry Accounting Books(hereinafter referred to as the “Park’s Book”) is the world’s oldest surviving double-entry accounting book, with records spanning 26 years around the turn of the 20th century. The Park’s Book contains accounting records related to monetary transactions, ginseng cultivation, rice farming, merchandise trading, and branch accounting. Since its discovery in 2005, prior researches have analyzed various aspects of the Book, excluding merchandise transactions. This paper is the first study to conduct an in-depth analysis of merchandise inventory accounting in the Park’s Book. The findings will provide valuable insights into the realities of this important cultural heritage, the evolution of accounting history, and the economic conditions of that time. This study systematically analyzes journal entries, postings, financial closing, and reporting related to merchandise transactions. Also, this study identifies differences from modern practices of inventory accounting. Merchandise transactions in the Park’s Book can be classified into sales through branches and direct sales by the head office. In branch transactions, merchandise sales were aggregated into the head office’s branch account, with annual sales income calculated and equally divided between the branch manager and the head office. The head office’s half-share of the income was reported under the branch income item in the hoegaejimjakcho(회계짐작초) which is similar to income statement. For direct sales by the head office, a maedeuk account (매득계정) was created to record purchases and sales, as well as to calculate inventory and sales income. Since the maedeuk account recorded both purchases and sales, it functioned as a mixed inventory account. In this case, sales income was primarily calculated after inventory was depleted. For frequently traded and high-volume merchandise(e.g., grains, textiles, and salt), separate income accounts were created for each product, and their sales income were reported as credit items in the juhoegae(balance sheet). On the other hand, for high-value and infrequently traded goods(e.g., deer antlers and white ginseng), income was reported in the hoegaejimjakcho rather than the juhoegae. Additionally, for precious metals such as gold and silver, sales income was not calculated; instead, the balance of the maedeuk account was periodically withdrawn as an owner’s withdrawal. The Park’s Book did not compile a comprehensive income statement for merchandise transactions but rather managed income separately by product. Particularly, the practice of reporting sales income for key high-volume products as independent account items in the juhoegae suggests an intentional effort to track the profitability of these goods at a glance. A significant difference between the Park’s Book and modern accounting is that a 15% annual cost of capital was added to both debit and credit amounts in the maedeuk account from the time of the transaction until income calculation. Consequently, the recorded sales income corresponds to the modern accounting concept of residual income. Recognizing cost of capital in the maedeuk account aligns with other accounting areas of the Park’s book, such as ginseng plantation, branch business, and capital investment. The inclusion of cost of capital suggests that these accounts were considered investments: debit balances represented investments, while credit balances represented investment recoveries. If, at the time of closing, a debit balance remained, it was classified as an investment loss, whereas a credit balance indicated an investment gain. The explicit recognition of cost of capital in the Park’s Book is a globally unique case in accounting history. The concept of opportunity cost was first introduced by French classical economist Frédéric Bastiat in 1848, later named “opportunity cost” by Austrian economist Friedrich von Wieser, and incorporated into accounting by Ronald Coase in 1938. Since the development of the Capital Asset Pricing Model (CAPM) in the 1960s, the opportunity cost concept has been widely used in economics, business, and accounting. The fact that the Park Young-jin Family systematically incorporated capital costs into double-entry accounting books around 1900 demonstrates the pioneering financial mindset of Gaeseong merchants. To calculate sales income of the Park’s Book in modern accounting system, adjustments must be made based on this study’s findings. First, capital costs must be removed from product-specific income, as modern accounting recognizes only historical costs. Second, income from precious metals— which were accounted for as inventory but not explicitly recognized as sales income—should be calculated and added. Third, in years when inventory had not been depleted before the fiscal year-end and sales income was not calculated, separate income calculations must be performed. Additionally, for branch-related income, capital costs should be removed, and expenses such as bill discount fees should be reclassified as non-operating expenses instead of purchase-related expenses. During this research, potential areas for further studies were identified. The journal entries contain price data, which could serve as primary historical sources to estimate the cost of living during the decline of the Joseon Dynasty. Grains, textiles, and salt, being essential goods traded over long periods, can provide reliable insights into inflation and economic conditions of the time. Future research on these aspects is highly anticipated. Additionally, the interest rate fluctuations recorded in monetary transactions could be valuable research material for economic history.