The Index of Domestic Production is a quarterly indicator showing changes in the volume of production over time of resident manufacturing establishments at the national level.
Scope of Data
The Index of Domestic Production is a sample survey of 151 establishments selected from the 1995 register of business establishments. The survey collects data on the revenues, employment, hours worked, and earnings as well as the quantities and values of the main products produced and sold for each of the establishments in the sample.
The Index of Domestic Production follows the Trinidad and Tobago System of Industrial Classification (TTSIC) which is essentially a modified version of the United Nations International System of Industrial Classification (ISIC).
The Index is calculated from the Value of Goods Produced or Sold.
A stratified random sample was employed to derive one hundred and fifty-one (151) firms from the Annual Register of Establishments (1995) with employment of ten (10) or more persons across various industries.
The index is presented on a 1995 weight and reference base, using the Laspeyres formula. The quantities of the products within industries are weighted with their respective 1995 average unit values and the industry estimates are then aggregated using the 1995 value added weights derived from the annual national accounts estimates.
Estimates are calculated for non-response by using a year on year ratio of similar quarters to extrapolate the figure received for the relevant quarter in the previous year to obtain the relevant quarter in the current year or using the growth in the current quarter of production for similar firms for which a response was available.
Periodicity and Timeliness
Data is disseminated on a monthly basis, about three (3) months following the end of a reference period. In the event of this day being a public holiday or weekend, data will be disseminated on the next working day.
The data is compiled for the main sub-industries within manufacturing using the Trinidad and Tobago System of National Accounts Industrial Classification (TTSNA), but also cover the manufacturing establishments classified to other analytical sectors in the classification, such petrochemicals and gas refining. Users can compare the indices with the manufacturing component of the quarterly constant price GDP indices, as well as, with the corresponding annual GDP estimates published by the Central Statistical Office.