The UK government's statistical unit, formed by a merger of the Central Statistical Office and the Office of Population Censuses and Surveys in 1996. It is an executive agency of the Treasury responsible for collecting economic statistics for the government. Among its publications are the Monthly Digest of Statistics, Financial Statistics (monthly), Economic Trends (monthly), and UK National Accounts (the Blue Book; annual), UK Balance of Payments (the Pink Book; annual), and the Annual Abstract of Statistics.

• open economy
• open-end credit
• open-ended investment company
• open-end trust
• opening bank
• opening prices
• opening stock
• open interest
• open-market desk
• open-market operations
• open-market value
• open-mouth operations
• open outcry
• open position
• open years
• operating budget
• operating lease
• operating profit/loss
• operating risk
• operating statement
• operating target
• operational gearing
• operational leverage
• operational risk
• OPIC