The coronavirus pandemic and related economic worries drove a steep drop in market capitalization during the first quarter of 2020 among the top 20 U.S. utilities covered by S&P Global Market Intelligence.

These companies recorded a total market capitalization of $682.87 billion as of March 31, compared with $783.97 billion as of Dec. 31, 2019.

Allentown, Pa.-headquartered PPL Corp. posted the largest drop at 31.2% but remained at the 15th spot with a market cap of $18.95 billion.

During the quarter, the company saw the U.K. exit the European Union, which executives hope will stabilize the market for its utility business there.

"We still have the risk of Brexit that is keeping the markets a bit jittery," PPL Chairman William Spence said in a Feb. 14 earnings call. "I think that as we look forward, particularly as we get through 2020, it's very likely that we'll know a lot more about where Brexit ultimately lands and what the currency landscape looks like for sure."

Spence plans to step down June 1 and become the nonexecutive chairman of the company's board. Vincent Sorgi, who serves as president and COO, will succeed Spence.

On March 31, PPL updated its risk factor disclosure as a result of the coronavirus outbreak to say it cannot predict if there will be a material impact to its financial positions, results of operations or cash flows.

California utilities Edison International and Sempra Energy also saw large drops in their market caps. On March 19, the Golden State became the first to issue a stay-at-home order to contain the spread of the coronavirus.

Edison International moved down to the 14th spot with a market cap of $19.87 billion as of March 31. Starting the quarter with shares trading in the low $70s, the company's stock price entered the high $60s on Feb. 27, when it released earnings. The stock price has been on a downward trend since then, closing at $54.79 on March 31.

Mizuho Securities USA LLC said in a recent report that investors will return to Edison International stock because it is relatively cheap compared to the utility group as a whole.

Edison International is among those utilities that have been bolstering liquidity in the face of the pandemic. On March 23, it requested full access to its $800 million term loan facility. According to S&P Global Market Intelligence data, Edison International has $400 million of senior debt maturing in 2020.

Sempra's market cap saw a 25.2% drop, ending at $33.04 billion March 31.

Prior to the coronavirus-related sell-off, the utility's stock was already on a downward trend, driven by its midstream exposure. Sempra's stock closed at $127.76 on March 9, a day after Saudi Arabia slashed the price of its crude exports and set off a price war with Russia. On the prior trading day March 6, Sempra stock closed at $141.87.

But Mizuho indicated in a separate investor note that Sempra seemed to have overcome investor concerns during the latter part of March.

DTE Energy Co., another utility with midstream exposure, recorded a 26.7% drop in market cap as of March 31. With an $18.29 billion market cap, it fell to 17th place in the list.

"The growth prospects for utilities with cyclical non-utility activities are partially tied to macroeconomic factors. Hence, utilities with these higher-risk businesses, including those with exposure to construction services or midstream, may see faster downturns in the cycle in a prolonged outbreak," S&P Global Ratings said in a March 19 research note.

NextEra Energy Inc. remained the only company on the list with a market capitalization of over $100 billion. It also registered the smallest decline, with its market cap falling 0.6% to $117.65 billion.

NextEra subsidiary Florida Power & Light Co. recently issued $1.10 billion of first mortgage bond for general corporate purposes, including repaying its outstanding commercial paper obligations. In assigning an AA- rating on the bonds, Fitch said March 26 that it expects the coronavirus to have a limited impact on FPL.

FPL is the largest rate-regulated utility in the U.S. as measured by retail electricity produced and sold. According to S&P Global Ratings, most regulated utilities are well positioned to handle the immediate impact of the pandemic.

"[T]hey provide an essential service to consumers and businesses, most of whom will continue to rely on the steady supply of utility services. This means that most regulated electric, gas and water utilities are likely to be insulated since they mostly provide service to residential customers," Ratings added.

Although investors generally consider utilities a safe haven, all 20 companies in the list recorded quarter-over-quarter declines. Overall, the industry median decreased 15.8% from the 2019 fourth quarter.

Energy and utility stocks were among the worst performers in February. However, the S&P 500 utility indexes outperformed the broader S&P 500 index for the first quarter, which posted a total negative return of 19.6%.

The S&P 500 Electric Utilities Sub Industry index recorded a negative return of 12.0%, the S&P 500 Utilities index saw a decrease of 13.5%, while the S&P 500 Multi-Utilities index declined 16.1%.

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