An earthquake struck the area around Norman, Oklahoma this week, breaking windows and causing walls to crack. According to officials it was the second strongest earthquake in the state’s history. Geological records show only a handful of earthquakes in the state’s history have ever been strong enough to cause damage to structures. According to The Oklahoman, there have been 200 earthquakes in the state this year, but only 60 have been strong enough to be felt by residents.

After this week’s strong quake, many homeowners were surprised to learn that their homeowner’s insurance policy wouldn’t cover damage caused by the earthquake, according to KOCO. “Lately, they’re coming one, two, three times a week,” a Choctaw resident who bought earthquake insurance in January told KOCO.

Earthquake insurance can be purchased from most major companies for a relatively low cost. “In the last year, we’ve sold more earthquake policies than the last 17 years prior to that I’ve been an agent,” Farmers Insurance agent Scott Streller told KOCO. “For every $100,000 of coverage on a house, a rough estimate might be $150 a year.”

An earthquake struck California earlier this week with the epicenter shaking rural Baja California. While the 7.2 magnitude did some damage, it was not widespread. However, the natural disaster did bring to light that few Californians carry earthquake insurance. In fact, according to KPBS, only 12% of California homeowners have earthquake insurance. “California homeowners, in this most recent event, basically dodged the bullet,” said Glenn Pomeroy on KPBS. Pomeroy is the CEO of the California Earthquake Authority, which is a state-run non-profit that provides 70% of the earthquake insurance in California. “Let’s say the 7.2 that happened on Sunday happened under Los Angeles,” Pomeroy said. “We would see massive destruction. Homes destroyed. Infrastructure badly damaged.”

In 1994, following the costly Northridge Earthquake, California leaders created the earthquake authority which now has the ability to cover billions of dollars with of earthquake damage claims. But in order to receive it, homeowners must purchase policies and the majority do not. Think you’re covered by your homeowner’s policy? Not so says Pomeroy. Most do not cover earthquake damage. “Keep in mind that FEMA grants usually top out at about $30,000,” Pete Moraga told KPBS, a spokesman for the insurance industry in California. “And if you get or qualify for a low-interest loan, it’s still a loan and you’re going to have to pay it back.”

So how much can an earthquake insurance policy cost? Experts say if your house would cost $200,000 to replace, you would have to pay $30,000 out of pocket before you get any insurance money. That means the insurance often only covers cases of extreme damage, unlike what occurred as a result of the recent California earthquake. The annual cost for a policy can be as much as $1,000 a year in places that are more likely to get hit. But experts say other locations can cost just a few hundred dollars a year. However, some believe homeowners are better off putting that money towards improving their current home rather than buying policies. According to Pat Abbott, professor at San Diego State,”For most people they are better off spending even a few thousands of dollars strengthening their existing homes, and remove problems they have, at a cost less than the deductible on their insurance policy anyway.”