In India, the mammoth task of measuring GDP is undertaken by a central government ministry. This Ministry, with the help of various government departments of all the Indian states and union territories, collects information relating to total volume of goods and services and their prices and then estimates the GDP.

Introduction:
Gross Domestic Product (GDP) is a crucial economic indicator that measures the overall economic activity within a country. It is used to assess the size and growth rate of an economy. The task of measuring GDP is undertaken by various entities depending on the country's political structure and administrative divisions.

State Government:
- The state government does not typically measure GDP on its own. However, it may collect data and provide inputs to the central government for calculating GDP.
- The state government may be responsible for collecting data on state-level economic activities such as agriculture, industries, and services. This data can be useful in estimating the regional contribution to the overall GDP.

Provincial Government:
- The term "provincial government" is often used interchangeably with the state government in different countries.
- Similar to the state government, the provincial government may collect data on regional economic activities and provide it to the central government for GDP calculation.
- In some countries, provinces or regions have a certain level of autonomy, allowing them to calculate and report their regional GDP. However, this data is usually consolidated by the central government to calculate the national GDP.

Central Government:
- The central government is primarily responsible for measuring GDP in most countries.
- It establishes statistical agencies or departments that collect and analyze economic data from various sources, including the state and provincial governments.
- The central government ensures uniformity and consistency in GDP measurement across different regions of the country.
- It sets guidelines and methodologies for data collection, estimation, and calculation of GDP.
- The central government brings together data on consumption, investment, government spending, and net exports to calculate the national GDP.

Conclusion:
In summary, the task of measuring GDP is primarily undertaken by the central government. While state and provincial governments may collect relevant data, they usually provide it to the central government for calculating the national GDP. The central government plays a crucial role in establishing guidelines, collecting data, and ensuring consistency in GDP measurement.