Consumer confidence deteriorated for a second successive month in September. At minus 17.8, the flash estimate was down from August's final minus 16.0 and nearly 2 points below the market consensus. It was also the worst reading in half a year.

According to the EU Commission's measure, household confidence has been broadly flat since April. Still, the September drop was the steepest since last November and leaves the gauge well short of its minus 11.5 long-run average. As such, prospects for consumer spending remain poor. More generally, today's update puts the Eurozone RPI at minus 25 and the RPI-P at minus 39. Both measures show overall Eurozone economic activity running much cooler than market expectations, a characteristic that could well be reinforced by yesterday's ECB tightening.

Consumer confidence in September is expected to hold steady at minus 15.9 after August's nearly full point drop to minus 16 which was the first decline since March.

Compiled by the European Commission, the flash consumer confidence index is a broad measure of consumer sentiment. It is based on monthly surveys of consumers from all the European Union countries. The survey probes into consumers' perceptions towards their past and expected future financial conditions, as well as their feel of the economy overall. This includes topics such as major purchase intentions for the next year, savings intentions, home improvements, purchase of a car, prices and unemployment, among others. This flash measure is based on only partial data and provides an early guide to the final index, published around a week later as part of the full Economic Sentiment survey.

The pattern in consumer attitudes can be a major influence on stock and bond markets. Consumer spending drives the lion’s share of the economy, and if the consumer is not confident, she will not be willing to pull out the big bucks. This Consumer Confidence survey offers key confidence data across the European Union and the European Monetary Union. Consumer confidence impacts consumer spending which affects economic growth. For stocks, strong economic growth translates to healthy corporate profits and higher stock prices. For bonds, the focus is whether economic growth goes overboard and leads to inflation. Ideally, the economy walks that fine line between strong growth and excessive (inflationary) growth.

Since consumer spending accounts for such a large portion of the economy, the markets are always eager to know what consumers are up to and how they might behave in the near future. The more confident consumers are about the economy and their own personal finances, the more likely they are to spend. The index is a broad measure of consumer confidence in the EU members and because of its coverage of all the EU countries it is highly regarded in the financial markets as a good indicator of the mood of consumers in each country. It is also normally a good indicator of quarterly GDP.

Data are available for each country and are aggregated for both the EMU and EU. The data are seasonally adjusted and defined as the difference (in percentage points of total answers) between positive and negative answers. The survey is conducted by the European Commission rather than Eurostat, the compiler of most other EMU data and measures consumer confidence on a scale of -100 to 100, with -100 indicating extreme lack of confidence, 100 indicating full confidence and 0 indicating a neutral opinion. The long-term average of the series is around -14.