Construction and seasonal patterns of Islamic Hijri calendar monthly time series : an application to consumer price index (CPI)‎ in Pakistan

الملخص EN

Time series data are compiled and analysed in aceordanee with Gregorian calendar, gi¥en its world-wise use.

This paper presents a simple method of constructing time series in accordance with Hijri Calendar from an already compiled Gregorian time series, ?reliminary seasonal analysis of Hijri time series for CPI in Pakistan provides new insights of price behavior that depends both on Gregorian and Hijri seasonality.

A spliced series of monthly CPI from January 1976 to December 2008 spanning 33 Gregorian years (396 Gregorian months) is used to capture a full cycle of 34 Hijri years (408 Hijri months).

Method presented is general and can be used to construct and analyse any variable of interest.

Paper proposes that statistical agencies and central banks of Islamic countries should also compile data according to Hijri Calendar, in addition to existing compilation according to Gregorian calendar.

This will add to a better understanding of socioeconomic behaviours in Islamic countries