Consumer confidence returned to levels not seen in 18 months in September, the latest figures from Nationwide show.Over the course of the month, the consumer confidence index rose by six points to hit 71, while the expectations index rose to 106, up nine points.Commenting on the figures, Mark Saddleton, head of economic and market analysis, said that the gains had been far stronger than in preceding months, with the headline index now at its highest level since April 2008.However, he added: "Consumers' assessment of the present situation is still fairly downbeat and, while they do appear to be optimistic for the future, it is likely that any recovery will continue to be sluggish."The building society's interest rate prediction poll showed that 95 per cent of analysts believe the Monetary Policy Committee will hold this week, while five per cent anticipate a 0.25 per cent hike.The base rate currently stands at 0.5 per cent, the lowest it has been in the 315-year history of the Bank of England.