Important characteristics of index numbers ?

1. Base year: Index numbers are usually calculated with reference to a base year, which is assigned a value of 100. All subsequent values are then expressed relative to this base year.

2. Weighting: Index numbers often involve weighting different components based on their importance. This ensures that the index accurately reflects changes in the overall value of the items being measured.

3. Time period: Index numbers are typically calculated over a specific time period, such as a month, quarter, or year. This allows for comparisons to be made over time and trends to be identified.

4. Relative measure: Index numbers are a relative measure that compares the value of a variable at different points in time. They do not provide an absolute measure of the variable.

5. Percentage change: Index numbers are often expressed as a percentage change from the base year. This allows for easy comparison and interpretation of the data.

6. Uses: Index numbers are commonly used in economics, finance, and statistics to track changes in prices, wages, production, and other economic variables. They are also used to compare the performance of different entities or sectors.

7. Accuracy: Index numbers should be calculated accurately and consistently to ensure that they provide a reliable measure of the variable being tracked. Errors in calculation can lead to misleading results.

1. Purpose: An index number should be constructed for a specific purpose, such as measuring changes in prices, wages, or production.
2. Base Period: The base period is the period against which all other periods are compared. The base period is typically chosen to be a period of stability or normalcy.
3. Formula: The formula used to calculate the index number should be clearly defined. The formula should be based on a sound statistical method.
4. Weights: The weights used in the index number should reflect the relative importance of the items being measured. The weights should be based on a reliable source of data.
5. Scope: The scope of the index number should be clearly defined. The scope should include the items being measured and the geographic area being covered.
6. Timeliness: The index number should be published in a timely manner. The timeliness of the index number is important for users who need to make decisions based on the data.
7. Revisions: The index number should be revised as new data becomes available. Revisions are important for ensuring that the index number is accurate and up-to-date.
8. Accuracy: The index number should be accurate. The accuracy of the index number is determined by the quality of the data used and the statistical methods used to calculate the index number.
9. Comparability: The index number should be comparable to other index numbers. The comparability of the index number is important for users who need to make comparisons between different periods or different countries.

Describe double fortilization and triple fortilization