You hear a lot of companies touting four or five 9’s for their Uptime.

Then yearly downtime is calculated as:

• 90% – 876 hours
• 99% – 87 hours & 36 minutes
• 99.9% – 8 hours & 45 minutes
• 99.99% – 52 minutes & 33 seconds
• 99.999% – 5 minutes & 15 seconds