Over the past 3 years, a cloud service has been unavailable for a total of 36 hours, primarily due to a denial of service attacks. Additionally, the physical server hosting the cloud service was hacked and the service had to be rebuilt and migrated. It took the cloud provider 10 days to replace the server and for the cloud service to become operational again. Based on these statistics over the past 3 years, what is the availability rating of the cloud service?

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