1. Revision of National Accounts Time Series in the Netherlands
Ruurd Schoonhoven (
Gert den Bakker, Bram de Boo, Ruben van der Helm
Statistics Netherlands

2. Time series revisions in the Netherlands
Systematic time series revisions :
- after benchmark revisions of 1977, 1987, 1995, 2001
for supply and use (and I/O) tables, sector accounts and labour accounts
Different methods were used ….
…. with different costs (time, resources) …
…. and with different quality of results
How to proceed in future?

3. Suitability criteria for time series revisions
Resources
Time
Quality
Transparency
Flexibility

4. Approaches to time series revisions
1. Annual backward calculation
2. Benchmark years and interpolation

5. I. Annual backward calculation
I.1 From microdata, with new concepts and classifications (‘from scratch’)
I.2 Adjustments superimposed on balanced pre-revision data
I.3 Linking pre-revision (or revised) growth rates to results for revision year

6. II. Benchmark years and interpolation
II.1 Benchmark years ‘from scratch’
II.2 Benchmark years by superposition of adjustments on balanced pre-revision data
Intervening years by interpolation with pre-revision (or revised) growth rates

7. The 2001 time series revision
Conceptual revisions superimposed on pre-revision data year by year (I.2)
Statistical revisions interpolated between benchmark years (II.2)
Balancing of the results, year by year from 2000 back to 1969/1980
Strict process, good quality results, but (again) required much time and resources…..

8. Requirements for future time series revisions
Harmonisation of revision policy within EU
Users want revised time series faster
Budget reduction

9. Points of consideration (1)
EU regulations: I/O tables back to 2000, main aggregates back to 1980
Main user: detailed >30 yr time series

10. Points of consideration (2)
From scratch or using pre-revision results
Working level of detail
Compiling the time series in parallel with the revision year

11. Points of consideration (3)
How to avoid (reduce) the need for year-by-year balancing?
Automatic balancing methods

12. Discussion
International harmonisation of revision policy for time series?
Inventory of methods currently used in different countries