Indices are revised periodically considering the increase in the prices of goods. With this, old indices will be replaced by the new versions of indices. Therefore, when new series of indices are published with 2011-12 = 100 as the base, the old series of 1998-99 = 100 will become outdated. That does not mean that we should also redo the Dearness Allowances based on the new series, but we can continue to use the same base of the index. There will be a linking factor attached to the index number, which can be used to get the index number of the previous base. For example, the linking factor for Ernakulam district is 2.03 under the new series, and the CPI is 139. Multiplying 139 by 2.03, we will get the CPI of Ernakulam district of Kerala under the immediate previous base, i.e., 1998-99 = 100, and that is 282. Similarly, the linking factor of 1998-99 for the previous index number (1970 series) is 9.92. An establishment following the old index can get the CPI in the old series by multiplying 9.92 by the 1998-99 series.
An existing establishment calculating the DA using the 1998-99 series can follow the same series until a new DA is fixed by merging a portion of the DA with the basic pay of employees. The Statistics department usually publishes CPIs based on two series, current as well as old series. If the old CPIs are not available, you can calculate it by multiplying the linking factor with the new CPI. The ultimate result will be the same.
Example:
DA is based on CPI under the 1998-99 series.
DA is Rs 24.90 per point above 130 points.
The establishment is situated in Ernakulam district.
As per the information available, the CPI for Ernakulam under 1998-99 is 282.
Therefore, the DA will be 282-130 X 24.90 = Rs 3785.
Suppose that the establishment follows the new series, i.e., 2011-12 = 100, then the DA will be as follows:
CPI under the new series: 139.
DA will be available for 9 points, that is the number of points above 130 points will get DA at the rate of Rs 24.90 and the amount of DA for the month will be Rs 224 {(139-130) X 24.90}.
Following the new series without adjusting the basic salary will lead to a heavy loss to workers. Therefore, before we switch over to the new series, we have to revise the Basic salary by increasing it by the amount of DA lost. Alternatively, we can continue to follow the old series of indices.
Madhu.T.K