When the enterprise's construction in progress is expected to be impaired, such as the construction in progress that has been shut down for a long time and is not expected to start again within 3 years, the asset impairment reserve should also be accrued according to the above principles. The original "Accounting System of Joint-stock Companies-Accounting Subjects and Accounting Statements" stipulated that joint-stock companies should make provision for four impairment, namely, provision for bad debts of accounts receivable, provision for inventory depreciation, provision for short-term investment depreciation and provision for long-term investment depreciation. When a joint stock limited company implements the Accounting System for Business Enterprises, it needs to increase the provision for impairment of fixed assets, projects under construction, intangible assets and entrusted loans. According to the Ministry of Finance 17 Document "Provisions on Policy Cohesion of Implementing Enterprise Accounting System", the provision for impairment of fixed assets, impairment of construction in progress, impairment of intangible assets and impairment of entrusted loans caused by the implementation of enterprise accounting system by joint stock limited companies is treated by retrospective adjustment method. The original sub-sector accounting system only needs to make provision for bad debts of accounts receivable, and the enterprises that originally implemented the sub-sector accounting system will cause a comprehensive adjustment of the asset impairment provision policy when implementing the enterprise accounting system. ① Adjust the provision policy for bad debts. Need to adjust the scope of bad debts, from accounts receivable to accounts receivable and other receivables; The accrual method can be changed from the percentage of accounts receivable balance method to any one of the percentage of accounts receivable balance method, accounts receivable aging analysis method and sales percentage method; The proportion of bad debts was changed from the original unified national regulations to the enterprise's own determination according to the actual situation. ② Seven new provision for asset impairment were added, namely, provision for inventory, short-term investment, long-term investment, fixed assets, construction in progress, intangible assets and entrusted loan depreciation. Because the enterprises that used to be based on the industry implementation of accounting system have not yet implemented the Enterprise Accounting System, the state has not stipulated its specific connection mode. However, with reference to the Provisions on the Implementation of Corporate Accounting System and Policy Cohesion issued by the Ministry of Finance, it is very likely that other assets impairment reserves except bad debt reserves will be treated by retrospective adjustment method. Due to the adjustment of bad debt provision, accounting methods, accrual basis and accounting estimates have all changed. According to Article 131 of the Accounting System for Enterprises and Accounting Standards for Enterprises-Accounting Policies, Changes in Accounting Estimates and Correction of Accounting Errors, the future applicable method can be adopted, but its accounting treatment is relatively simple. When a company limited by shares implemented the original Accounting System of a company limited by shares-accounting subjects and accounting statements, the Ministry of Finance made it clear in the Notice on Printing and Distributing Supplementary Provisions on Accounting Treatment of the Accounting System of a company limited by shares that the provision of "four impairment reserves" by a company limited by shares was a change in accounting policy, and the retrospective adjustment method was adopted for accounting treatment. Therefore, it can be considered that enterprises that used to implement different industry accounting systems should adopt retrospective adjustment method when implementing the new enterprise accounting system.