Factors like real productivity growth, industrial specialisation and price changes influence regional economic performance over time. When the baskets of goods produced across regions are similar and/or inflation is low, the price effect will typically be negligible in explaining differences in regional performance, including over time. However, in nominal prices, the basket of goods produced can vary significantly across regions, especially in resource-rich regions and recent years have seen inflation reach its highest levels in decades. As such, the underlying assumption that regional economic performance can be assessed using national price indices has become increasingly strained. However, newly available data on regional price indices are now available, providing the scope to better understand relative performance across regions and how this translates into long-term economic growth.
This edition of Regions and Cities at a Glance introduces two significant methodological improvements: the use of regional deflators instead of national deflators in real gross domestic product (GDP) and gross value added (GVA) series at the large (TL2) and small (TL3) region levels and the use of regional consumer price indices (CPIs) to estimate real household incomes at the TL2 region level. Accounting for regional price changes provides a more accurate picture of economic growth drivers and changes in regions’ living conditions. These methodological improvements build on the recent release of regional deflators in European Union (EU) countries, complemented by data collection for other OECD countries.
Until recently, most countries did not produce volume estimates of regional GDP in basic prices that reflected the actual price changes of GDP in regions. Volume estimates, where available, were derived using national GDP deflators. While most countries do not currently produce regional estimates of GDP in volume terms using actual price change data observed by economic actors resident in the region, many are now generating volume estimates of regional GDP in basic prices by deflating regional value-added in a given industry using the national deflator for that activity. Whilst not perfect, this significantly improves a whole economy’s national GDP deflator. Moreover, whilst there may be significant differences in the price of a given product across regions in a country, there is less likely to be a significant difference in the price change of that product across the country, which means that volume measures of regional GDP produced in this way can be considered robust.
The primary advantage of employing regional deflators is the enhanced accuracy in measuring real (or volume) estimates of economic activity across distinct regions. National deflators, which average price changes across the entire country, can hide significant regional disparities in price changes. Using regional deflators better accounts for actual price changes producers and consumers face in each region. This methodological refinement facilitates more informed policy making, enabling the development and implementation of strategies better tailored to the specific economic circumstances of individual regions.
However, the transition to regional deflators presents certain challenges. Collecting and maintaining accurate regional price data require substantial resources and sophisticated statistical methodologies. Variations in data quality and availability across regions can affect the consistency and comparability of regional deflators. Additionally, while regional deflators provide a more accurate local perspective, chain-linked measures can result in a loss of additivity between deflated subnational measures and the equivalent national totals. Despite these challenges, the benefits of adopting regional deflators – such as enhanced accuracy of regional economic analysis – outweigh the drawbacks, ultimately leading to more effective economic policies.
This section explains the concept of regional deflators and, to help illustrate their importance, compares economic indicators with previous series using national deflators. The first section focuses on output prices, the second on consumer prices.