Statistics

Seasonal variations are the changes in data patterns that repeat themselves over regular intervals such as months, quarters, or seasons.
These are caused by environmental, social, and cultural factors such as climate changes, festivals, holidays, and weather conditions.
For example, ice cream sales peak in summer and decline in winter, or tourism increases during holidays.
Such effects repeat every year and follow a known pattern.
These are distinctly different from secular trends (long-term), cyclic variations (economic cycles), or irregular variations (unexpected events).
Therefore, the correct classification for variations due to climate and festivals is seasonal variations.