Seasonal Adjustment of Ramadan Effect in GDP by Expenditures

One of the results of decomposition of time series data is the seasonal component. The seasonal component is a short-term periodic cyclical change with a period of less than one year. Moving holiday is a form of the phenomenon of the calendar effect. Moving holidays occur when certain celebration dates change from year to year due to differences in the calendar system used. This can affect seasonal patterns from time series data.Ramadan and Eid al-Fitr are examples of the phenomenon of a moving holiday. This celebration is set using the Hijr calendar so that when viewed on the Christian calendar it will experience a shift. The existence of Ramadan and Eid al-Fitr celebrations has a direct influence on macro consumption patterns, especially in countries where the majority of the population is Muslim, including Indonesia. Among the various data available, GDP Household Consumption Expenditures can provide an accurate picture related to the phenomenon of fasting and public consumption. This study discusses the analysis of seasonal adjustment data on GDP time series of household consumption of food and beverages consumption in the first quarter of 2010 - quarter IV 2018 using several treatments, namely, the application of the Ramadan effect, the application of the seasonal break effect, and the application of the two effects to conclude which treatment better applied to that data.