The Dow Jones index of major US shares has closed at an all-time record high, beating the previous record set in 2000, as oil prices continue to fall.
The Dow ended the day up 56.99 points at 11,727.34, having earlier also set a new intra-day record of 11,758.95.
The rise came after oil prices fell to their lowest level since February, on news of higher stocks and lower demand.
Economists say falling oil prices could boost consumer spending and buoy corporate profits.
The Dow Jones index has recently been hovering around its previous record close level of 11,722.98, which it set in January 2000.
Despite the rise, analysts reactions remained tempered, warning that it remains far from clear which direction the US economy will head.
"I think we break out to the all-time high, then we could get a blow-off correction off of that," said Doug Johnston of Adams Harkness.
Scott Wren, an analyst with AG Edwards & Sons echoed this: "It is a psychological boost. As far as the market goes it is a pretty narrow gauge of the stock market."
Lower petrol prices, coupled with greater confidence in the job sector, helped to boost consumer confidence unexpectedly in September.
Light US crude oil settled at $58.68 a barrel, a fall of $2.35, continuing Monday's drop.
Investors have welcomed the Federal Reserve's decision to freeze interest rates at 5.25% for two successive months.
Some analysts say this is a sign that inflation is under control.
When the index last hit its peak, the internet boom was in full swing. But the index later dropped to 7,286.27 in October 2002 before recovering.