Confusing Oracle/Sun Solaris OS Versioning

I'm always confused when I want to find out the exact release of the Solaris OS which I am working on.
If you do a "$ more /etc/release", you get something like below:

It's still very hard to relate 9/10 belongs to which release. I can relate more to U1, U2, etc... It's easier to track, at least for me.

Luckily, Wikipedia tracks it here.

• Solaris 10 1/06 ("U1")
• Solaris 10 6/06 ("U2")
• Solaris 10 11/06 ("U3")
• Solaris 10 8/07 ("U4")
• Solaris 10 5/08 ("U5")
• Solaris 10 10/08 ("U6")
• Solaris 10 5/09 ("U7")
• Solaris 10 10/09 ("U8")
• Solaris 10 9/10 ("U9")

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