COSCO SHIPPING Port's performance for the third quarter of 2021 is basically in line with our and market expectations. Although the throughput of the holding terminal declined slightly year over year, single-box revenue increased significantly, and the company's revenue for the third quarter of 2021 rose 9.5% year-on-year to $295.8 million. The steady increase in throughput from non-controlled terminals is also gradually driving COSCO SHIPPING Port's profits from joint ventures to increase. In the third quarter of 2021, the company's terminal operating profit increased 11.7% year on year, and due to other operating expenses, shareholders' net profit increased slightly by 0.2% year on year to US$86.14 million, which is basically in line with our expectations.
Operating efficiency has gradually improved, and the company's performance momentum continues under refined operation. In the first three quarters of 2021, we observed that, benefiting from operating costs and exchange rates, the company's single-box revenue increased significantly by 13.5% year-on-year, which led to an increase in the gross margin of a single box. Judging from the data, the overall gross margin of overseas terminals in the third quarter of 2021 increased by 2.6 percentage points year-on-year to 15.9%. There is still a certain gap compared to the 39.7% gross margin of its terminals in Greater China. Since there are many newly operated terminals overseas, we think there is still plenty of room for improvement in the profitability of the company's overseas terminals.
In the context of continuously strengthening the control of investment terminals, the company proposed the concept of single-box efficiency with a view to increasing single-box revenue and reducing single-box costs through strengthened operation and management measures. At the same time, it proposed to achieve 57 million equity throughput by 2025 (corresponding to a compound annual increase of 8.2%) and a reduction in single-box costs of 15%-20% (corresponding to a reduction of 3%-4% per year). Based on the company's current operating conditions and use of information technology, we believe it is moving towards its goals.
The company's financial situation is good, and its return on net assets is expected to increase as the terminal portfolio is optimized. On July 14, 2021, the company completed the acquisition of 20% of the shares in Red Sea Gateway Terminal (production capacity of about 5.2 million TEUs), making it an associated company. The merger of the Tianjin container terminal is expected to be completed by the end of 2021. We estimate that its throughput will exceed 8 million TEUs in 2021, which is expected to drive the company's equity throughput growth significantly.
Furthermore, the acquisition of Container Terminal Tollerort GmbH (CTT), located in the port of Hamburg, Germany, is also on schedule. Due to the terminal's superior transportation and ability to handle large container ships, we believe that through synergies with shipping companies, the terminal's throughput is highly guaranteed. Furthermore, CTT is already operating maturely, and the acquisition is expected to be directly profitable. As of the end of the third quarter of 2021, COSCO SHIPPING Port's cash holdings remained abundant, and the net balance ratio was moderate. We believe the company's financial situation is good. In the future, the company will continue to pay attention to purchasable projects in various regions and require that the internal rate of return of the underlying shares is at least double digits. We believe this shows that the company is paying more attention to improving return on assets when implementing terminal portfolio optimization strategies and anticipates that the company's return on net assets will benefit from this.
Valuations have fallen back to attraction and are highly defensive. As China's high import and export base decelerates, its impetus for the increase in company valuations is expected to weaken.
However, with the stock price correction, we think the company's valuation is still attractive. Although throughput growth slowed in the third quarter, due to the impact of various short-term factors, subsequent corporate throughput growth should be expected to return to moderate growth. In the future, the company's business growth will continue to be achieved through refined operation and terminal combination optimization. The company is characterized by a high dividend rate and has plenty of cash, so we think it is more defensive. Our current investment rating is “Buy” and our target price is HK$8.30.