基本法107

香港特別行政區的財政預算以量入為出為原則,力求收支平衡,避免赤字,並與本地生產總值的增長率相適應。

Basic Law Article 107 

The Hong Kong Special Administrative Region shall follow the principle of keeping the expenditure within the limits of revenues in drawing up its budget, and strive to achieve a fiscal balance, avoid deficits and keep the budget commensurate with the growth rate of its gross domestic product.