After concerns over the hurricanes faded off at the end of September, consumer optimism surged at the beginning of October, according to the Survey of Consumers conducted by the University of Michigan.

The Index of Consumer Sentiment Increased 6.3% from September’s 95.1 to 101.1 at the beginning of October. This is up a full 15.9% from the index’s 87.2 last year.

“Consumer sentiment surged in early October, reaching its highest level since the start of 2004. The October gain was broadly shared, occurring among all age and income subgroups and across all partisan viewpoints,” Survey of Consumers Chief Economist Richard Curtin said.

“The data indicate a robust outlook for consumer spending that extends the current expansion to at least mid 2018, which would mark the second longest expansion since the mid 1800’s,” Curtin said. “While the early October surge indicates greater optimism about the future course of the economy, it also reflects an unmistakable sense among consumers that economic prospects are now about as good as could be expected.”

An article by Jill Mislinski for Advisor Perspectives explains what this confidence level means historically:

The Michigan average since its inception is 85.4. During non-recessionary years the average is 87.6. The average during the five recessions is 69.3.

But Curtin explained that when consumers’ attitudes reach this level, it’s is usually an indicator that it’s the beginning of the end.

“This ‘as good as it gets’ outlook is supported by a moderation in the expected pace of growth in both personal finances and the overall economy, accompanied by a growing sense that, even with this moderation, it would still mean the continuation of good economic times,” Curtin said. “Although such an outlook is typically recorded in the late phase of an expansion, its occurrence is independent of the ultimate length of an expansion.”

The Current Economic Conditions index posted an increase of 4.2% from last month’s 111.7 and 12.8% from 103.2 last year to hit 116.4 at the beginning of October.

The Index of Consumer Expectations also increased significantly – 8.2% from 84.4 last month and a full 18.9% from 76.8 last year to hit 91.3 in October.

“Indeed, nothing in the latest survey indicates that consumers anticipate an economic downturn anytime soon – which contrarians may consider a clear warning sign of trouble ahead,” Curtin said.

“Nonetheless, consumers anticipate low unemployment, low inflation, small increases in interest rates and most importantly, modest income gains in the year ahead,” he said. “It is this acceptance of lackluster growth rates in personal income and in the overall economy that signifies that consumers have accepted, however reluctantly, limits on the pace of improving prospects for living standards.”

But this isn’t the message all experts received from the surge in confidence. One economist explained it could mean soft economic growth could soon rebound.

“The unexpected surge in the University of Michigan measure of consumer confidence index to its highest since 2004 provides further reason to think that, although real consumption growth may have slowed a little in the third quarter, it will pick up again before long,” Capital Economics Economist Andrew Hunter said.