...Rapid expansion in ASEAN has challenged the bank's capitalization and asset quality. Outlook: Stable The stable outlook reflects our expectation that Bank of China (Hong Kong) Ltd. (BOCHK) will maintain its high systemic importance in Hong Kong, and its close linkage to the creditworthiness of the wider Bank of China group over the next two years. The outlook also reflects our expectation that BOCHK will maintain its business and financial strength over the same time horizon, as reflected in its well-established market franchise, solid capitalization, and an above-average funding and strong liquidity profile. We view the likelihood of an upgrade as low over the next two years. We believe a downgrade of BOCHK is also unlikely over the next two years. We could lower the ratings on BOCHK if we observe a significant deterioration in the bank's capitalization and asset quality that results in a two-notch downward movement in its stand-alone credit profile (SACP), but we assign a low probability...