How devastating would a global cyberattack be on the world’s economy? Such an event could do more than $121 billion worth of damage according to a recent estimate by one of the world’s largest insurers.

Lloyd’s of London, in a report published along with cybersecurity analytics platform provider Cyence, found that cyberattacks on heavily relied on services like cloud platforms could lead to billions of dollars of losses around the world—costs on par with those associated with natural disasters.

Read: New Massive Global Cyber Attack Hitting Ukraine Banks, Government And Spreads Across Europe

The 56-page report published by the world’s oldest insurance firm found the next decade could be filled with cyberattacks that have catastrophic financial fallout for businesses and government alike.

The most likely scenario according to the report would be a malicious attack that takes down a major cloud service provider, resulting in massive amounts of lost data and information. Such an attack would result in an average estimated loss of $53 billion, but the damages could be as high as $121.4 billion.

For comparison’s sake, the devastation caused by Hurricane Sandy in 2012 caused an estimated $50 billion in economic losses. Hurricane Katrina in 2015 was estimated to cause $108 billion in losses, meaning a major cloud service attack could be more costly—though would likely not carry a death toll.

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The second-most likely threat laid out by the report considers the possibility of a large-scale attack against operating systems that could hit a huge number of businesses around the world. The “mass software vulnerability scenario” could cause damages of up to $28.7 billion.

Read: Petya Ransomware: How Businesses Can Prepare Against Similar Cyber Attacks

Such an attack is much easier to imagine in the wake of two major attacks that basically fit the bill laid out by Lloyd’s. WannaCry, a global ransomware attack that held hostage more than one million computers in more than 150 countries, started spreading in May and hit everything from major corporations to hospitals and even stop lights.

Just a month after that, an attack referred to as Petya began hitting computers in Ukraine and spread to more than 12,500 machines in more than 60 countries. The attack, originally believed to be another instance of ransomware, turned out to be a wiper designed to delete all files on an infected machine.

In both instances, the attack was spread due to an exploit discovered by the U.S. National Security Agency. The exploit, and several others, was stolen by an anonymous group of hackers known as the Shadow Brokers and made public.

“This report gives a real sense of the scale of damage a cyber-attack could cause the global economy,” Inga Beale, chief executive of Lloyd’s, said in a statement. “Just like some of the worst natural catastrophes, cyber events can cause a severe impact on businesses and economies, trigger multiple claims and dramatically increase insurers’ claims costs.”

The Lloyd’s report noted most losses from cyberattacks are not insured, which would leave governments and businesses on the hook if they were hit. The report estimated the uninsured gap could be as high as $45 billion for a cloud services attack and $26 billion for the mass vulnerability attack.