By Josh Zumbrun and Sarah Chaney 

Hurricane Harvey will distort measures of the U.S. economy in weeks and months ahead. Everything from jobless claims, which already surged in a report on Thursday, to gross domestic product and inflation, will be knocked off course by the storm.

The storm will make it difficult for economists to gauge the trajectory of the economy, with brief spikes across a wide range of reports. It will be hard to discern whether bad reports result from storm damage and then whether good reports owe to the effects of rebuilding. It could be well into 2018 before the storm's effects have fully washed out of the economic data.

Forecasters in The Wall Street Journal's survey of economists estimate the storm will affect the most important economic reports at the national level in the months ahead. They expect the storm to reduce the pace of job gains by about 27,000 jobs a month in the third quarter on average, followed by little change in the fourth quarter and then a boost of 13,000 in the first quarter 2018, as many people find work in the rebuilding process.

The growth rate of gross domestic product will fall by about 0.3 percentage points in the third quarter, they expect, followed by no effect on the fourth quarter, and an 0.2 percentage point boost in the first quarter of 2018.

"The devastation in the surrounding Houston area, America's fourth-largest city, will be significant enough to negatively impact activity and employment nationally, especially in the third quarter, but some of those effects will be transitory," said Chad Moutray, chief economist for the National Association of Manufacturers. "...I would expect the Houston economy and its all-important energy sector to be quite resilient moving forward."

Estimates of the storm's national economic impact remain preliminary -- and Hurricane Irma, which is currently headed for Florida, could exacerbate the effects. Beginning this week, a growing number of economic indicators will show Harvey's impact, from jobless claims, to inflation, to retail sales, to housing starts and beyond.

In the longer run, the storm is expected to have no lasting impact, with forecasts for gross domestic product, unemployment, inflation and other major economic indicators unchanged for 2018 overall, according to the survey of 56 business, financial and academic economists from Sept.1 to Sept. 5. In the months ahead, here is where economists say to watch for the storm's distortions.

Jobless Claims

Early evidence of the hurricane's impact on the U.S. job market came Thursday, when the Labor Department reported the largest one-week jump in initial jobless claims since the aftermath of superstorm Sandy in November 2012. It is likely only the beginning of a spike in unemployment filings.

In the weeks after Hurricane Katrina in 2005 and superstorm Sandy in 2012, jobless claims were highest not during the week of the storm, but two weeks after. Many who were out of work from the hurricane waited until the storm had passed to file their claims.

Compared with the week of the storm, initial jobless claims rose 23% in the second week after superstorm Sandy and 30% in the second week after Hurricane Katrina.

"Irma's right behind Harvey, so that could cause claims to spike again," said Ryan Sweet, director of real-time economics at Moody's Analytics.

Inflation

Measures of inflation will soon reflect Harvey's impact, with gasoline prices spiking due to disruptions to oil refineries in the Houston area. The national average gas price was $2.66 a gallon on Wednesday, according to the AAA, up from $2.35 a month ago.

Denton Cinquegrana, chief oil analyst of Oil Price Information Service, sees gas prices peaking near $2.75 before leveling off.

Energy prices make up 7% of the consumer-price index, with motor fuel accounting for nearly half of that. Already, the move in gas prices could raise the inflation rate by about 0.5%. With past major storms, the effect has faded within a few months.

Consumer spending

With gas prices up, consumers across the country will have less cash for everything else. Every penny increase in gasoline prices reduces consumer spending by $1 billion over the course of the year, according to Mr. Sweet of Moody's.

"Consumers are going to feel it in their pocket," Mr. Sweet said.

Consumer-spending measures may also show the impact of Houston being shuttered for so long. The city of Houston has nearly three million workers and produces about $500 billion a year of gross domestic product.

That is "a non-negligible economic impact, assuming 25% of Houston area output was idled for seven days," said Gregory Daco, chief U.S. economist of Oxford Economics.

Housing

Before the storm, Texas was on track for a 14% increase in housing starts this year, according to James Gaines, chief economist at the Real Estate Center at Texas A&M University.

In 2016, Houston alone accounted for about 4% of the nation's permitted housing. All that activity will grind to a halt as builders wait for construction sites to dry out, assess the market and compete for construction workers to rebuild and repair the city.

Household Wealth

Destruction of homes and businesses doesn't show up in gross domestic product, but it would show up in measures of household wealth. A complication from Hurricane Harvey is that many homeowners and businesses didn't carry flood insurance, meaning that a large share of the over $100 billion in estimated damage could reduce household wealth.

"With so many homeowners uninsured, this is more akin to a wipeout of assets such as one would expect from a stock-market crash," said Constance Hunter, chief economist for KPMG, the accounting firm."The effects are more negative and widespread."

But in a $19 trillion economy with 150 million workers, many of the effects will be hard to tell apart from the usual churning of such a large nation. Economic indicators can only measure so much of a storm's effect.

Ultimately, "the impact on individual lives will dwarf the economic dollar losses," said Lynn Reaser, a former Bank of America economist who is now a professor at Point Loma Nazarene University in San Diego.

--Laura Kusisto contributed to this article.

Write to Josh Zumbrun at Josh.Zumbrun@wsj.com and Sarah Chaney at sarah.chaney@wsj.com

 

(END) Dow Jones Newswires

September 07, 2017 10:14 ET (14:14 GMT)

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