Hurricanes Harvey and Irma swamped the job market in September, and now they’ve dented President Trump’s rating on the economy.

Trump’s grade on the Yahoo Finance Trumponomics Report Card dropped from A- to B+ in early October, based largely on the unexpected loss of jobs in the US economy the month before. Employers slashed 33,000 jobs in September, when economists had been expecting a gain of 80,000 or so. Manufacturing employment fell by about 1,000. It was the first net loss of jobs in the US economy in 60 months.

Those lost jobs pushed Trump’s grade one notch lower on our Trumponomics Report Card, which measures the economy’s performance under Trump compared with seven prior presidents, going back to Jimmy Carter in the 1970s, at the same point in their presidencies. We rate Trump and the other presidents on six key metrics, using data provided by Moody’s Analytics. Viewers are welcome to read and comment upon our full methodology. Here’s how Trump compares:

Job creation under Trump is now in the middle of the pack, with the economy adding more jobs under Presidents Bill Clinton, George H. W. Bush and Jimmy Carter, and performing worse at the 8-month point under Presidents Barack Obama, George W. Bush and Ronald Reagan. Here’s a breakdown of the latest grade for Trump and the job growth number for each of the seven presidents 8 months into their first term:

If economists are right and the job loss in September was largely the result of two destructive hurricanes, then the setback ought to be temporary and jobs should return. That would boost Trump’s grade back to the A range, as long as none of the other economic indicators deteriorated. Job growth under Trump had been relatively strong until the September numbers brought it down.

We’re not attributing the economy’s performance under Trump to any specific policy advanced by his administration. Trump largely inherited the economy we have now and is benefiting from a job market that has been healing from recession for 8 years. Yahoo Finance is running the numbers on the Trump economy every month because the president typically gets credit or blame for the health of the economy, no matter what the cause. The state of the economy will be an important factor in the 2018 midterm elections and the 2020 presidential campaign.

While Trump’s grade could rise again if job losses are temporary, it is also vulnerable to other possible economic developments. Stock values have been setting records day after day in 2017, and a downturn in stocks would bring Trump’s grade down with it, since the S&P 500 stock index is one of the indicators we track. If Trump’s tax-reform plan hits new roadblocks—which seems more likely every day—it could cut into confidence and spending. And a military confrontation in Korea, which Trump has been hinting at, would upend the global economy in unpredictable ways. The Trump economy probably has many more ups and downs ahead.