Base year adjustment for index series

[djhurio]

This refers only to index time series. For a base year the average index should be 100. This is true for the original data. However, after adjustment the average index for the base year for calendar or seasonal adjusted data is not 100 anymore. So, we do an extra adjustment (multiplication by a constant) to fulfil this requirement. We do it in Excel (VBA) or R.

Would it be possible to implement such feature for JDemetra+? The input required from a user would be:

• to select if base year correction should be applied;
• to choose a base year.

[CHMcLaren]

I would also support this. It could be made more general as well, as it is close to the annual NSA = annual SA approach for all years, e.g. where for index NSA if it is 100 already, this would do the same job.