1. National Accounts World Wide Exchange
Lars Thygesen, OECD
May 2007

2. OECD’s SDMX work Promoting SDMX as the world standard
Trying to generalise formats across domains
away from stove-pipes
Using SDMX in and out of OECD.Stat
SDMX web service
Joint External Debt Hub with BIS, IMF, WB
NAWWE
ComTrade with UNSD
Data sharing with IMF (and other IOs)
Education with Eurostat, UNESCO
Country pilots: data collection
May 2007

3. Rationale The idea Benefits to country's NSO
web based mechanism
report internationally agreed set of data
allow any authorised user to access data
international organisations agree
Benefits to country's NSO
One format and one operation for reporting
Automated generation of data from source
Built-in validation
Benefits to international organisations
Timely reporting
Complete reporting
No code misinterpretations
May 2007

4. Architecture: Data Flow OECD Web Server Web Application SDMX V 2.0
XML Schemas
XML Files
Validated
By Schema
<?xml version="1.0" encoding="UTF-8"?>
<xs:schema xmlns:xs="
<xs:element name="Code">
<xs:complexType/>
</xs:element>…….
XML Files
Navigation
Structural XML
<?xml version="1.0"?>
<GenericData>
<Value>CANADA</Value>
</Data> ……
Transformed XML
<?xml version="1.0"?>
<GenericData>
<Value>STRUCTURE</Value>
</Data> ……
<?xml version="1.0"?>
<GenericData>
<Value>STRUCTURE</Value>
</Data> ……
Upload to
ANA Database
or Output to
Other Format
Data and Metadata
Structure Definitions
Process Checks for
Updated XML Files
<?xml version="1.0"?>
<GenericData>
<Value>AUSTRALIA</Value>
</Data> ……
NSOs create SDMX-ML 2.0 data and metadata files in the Generic message format.
OECD web application validates NSO data files against official SDMX V 2.0 XML schemas.
Structural XML on OECD web server establishes Data and Metadata structure definitions including dimension concepts and related code lists based on a joint questionnaire with EuroStat.
Process automatically checks NSO data file URLs for updates on a periodic basis.
If files have been updated, OECD caches a new copy onto the web server for feeding the web application interface. This is purely for performance reasons as it is inefficient to load large XML data streams over HTTP at run-time; therefore files are cached onto the web server for fast loading.
Structural XML content drives the web applications navigation and usability.
When dimensions are selected from the structural XML the cached NSO data XML is accessed to load the statistical content into the interface.
The web application allows the transformation of the data XML into formats required for loading into the internal database or to output in other formats such as GESMES, Excel, and CSV.
The overall process provides efficiency gains for collecting, validating and loading National Accounts data at the OECD.
Cached Data XML
XML Files
Copied to
Server
XML Files
Content
<?xml version="1.0"?>
<GenericData>
<Value>CANADA</Value>
</Data> ……
<?xml version="1.0"?>
<Genericdata>
<Value>AUSTRALIA</Value>
</Data> ……
May 2007

5. Prototype V1: Web Interface
Previous version of the NAWWE pilot was based on SDMX-ML V 1.0
The interface served as a proof of concept to load NSO data XML in a standard format by selecting data structure criteria from the structural XML.
The new version of NAWWE capitalises on improvements with version 2.0 of the SDMX standards. The most important of these improvements are:
Definition of hierarchical dimension structures (e.g. ISIC Rev 3 industry classification)
The ability to structure and report reference metadata attached at any level of the data structure (i.e any combination of dimension members from ranging from the entire table to an observation.
Data selection criteria is driven from the Structural XML
Data content is driven from the copied NSO XML data files
Dimension criteria and countries can be combined for output
May 2007

6. Joint Eurostat/OECD questionnaire
Contains 48 tables
New version starting 2007
To be used by OECD from 2007
Yet to be formally adopted by EU
May 2007

7. The NAWWE schema http://stats.oecd.org/nawwe/
SDMX-ML v/2 generic message
with 17 common dimensions + table no.
codelists based on international standards
Will accommodate yearly as well as quarterly national accounts
But limited now to annual accounts
May 2007

8. Status spring 2007
Countries: Australia, Canada, US, New Zealand, Mexico
Organisations: OECD, ECB, IMF
“Almost final” specification of questionnaire end 2006
Data Structure Definitions for all tables
but only 11 of them specified as tables
Metadata Structure Definition
using SDMX Cross-Domain Concepts
May 2007

9. Next steps Four countries expected to report 2007
BEA already shows many OECD tables on its web site
Process:
Adapt these tables to new questionnaire
Replace these tables by NAWWE tables
May 2007

10. The End Comments and questions lars.thygesen@oecd.org Tour Europe
May 2007