Chained calculation
In the context of price indices, a chained calculation means a calculation is done one increment at a time and then multiplied to produce the index for the target date. The increment is usually a year. A chained calculation is in contrast to a fixed-base calculation that calculates the target in one shot. In this sense a chained calculation is "path-dependent".
The chained version of an index may require more data points in order to calculate the index for all years. To give an example, the fixed-base version of the Laspeyres index does not require quantity data for all years (only for the base year), even to calculate the index for all years [1]. In contrast, the chained version requires quantity data for all years.
Devec database
Some data in the devec database use chained values. From the MySQL prompt:
select metric,units from data where region = 'Japan' and (metric REGEXP 'chained' or units REGEXP 'chained') group by metric,units;
This returns:
+-------------------------------------------+---------------------------+ | metric | units | +-------------------------------------------+---------------------------+ | Expenditure-side real GDP at chained PPPs | 2005 international dollar | | Expenditure-side real GDP at chained PPPs | 2011 international dollar | | Output-side real GDP at chained PPPs | 2005 international dollar | | Output-side real GDP at chained PPPs | 2011 international dollar | +-------------------------------------------+---------------------------+