WASHINGTON — American consumers’ confidence has slipped after reaching an 18-year high last month. The Conference Board said Tuesday its consumer confidence index fell to 127.7 in March. That was down from 130 in February, which was the highest level since November 2000.

Consumers were less optimistic in March as their assessment of business conditions declined, the Conference Board said. Their short-term expectations – including their outlook for the stock market – also declined, although overall expectations remain favorable. The percentage of survey respondents saying that business conditions are good increased from 36.5 percent to 37.9 percent, but those saying business conditions are bad also rose, from 11.3 percent to 13.4 percent.

The business research group’s index measures consumers’ assessment of current conditions and their outlook for the next six months.