Seasonality
Also called: Seasonal variation · Topic: Economic Data: Census, NSS, Surveys and Statistical Tools · NCERT: Class 7, Ch 12 "Understanding Markets"; Class 9, Ch 9 "The Price Puzzle: What Drives the Market"; Class 11, Ch 4 "Presentation of Data"; Class 11, Ch 8 "Use of Statistical Tools"
Meaning
Seasonality is a regular pattern in data that repeats within a year, such as every harvest, season or festival. Because of it, comparing one month with the month before can mislead. So economic figures are often compared year-on-year (with the same month last year), or published after seasonal adjustment, which removes the regular pattern.
Example
Vegetable prices rise every monsoon, and crop arrivals peak after the kharif and rabi harvests. This is why CPI and IIP are usually quoted year-on-year.
Don't confuse with
- Cyclicity: cyclical patterns, such as business cycles, take more than one year to repeat.
Related concepts
- Time series
- Trend
- Cyclicity
- Compound annual growth rate
- Leading indicators
- Purchasing Managers' Index