What if I was outside the USA for 1 year or longer?
In almost all cases, if you leave the USA for 1 year or more, you have disrupted your "continuous residence."* This is true even if you have a Re-entry Permit.
If you leave the USA for 1 year or longer, you may be eligible to re-enter as a Permanent Resident if you have a Re-entry Permit. But none of the time you were in the USA before you left the country counts toward your time in "continuous residence".
Fortunately, if you return within 2 years, some of your time out of the country does count. In fact, the last 364 days of your time out of the country (1 year minus 1 day) counts toward meeting your "continuous residence" requirement.

*"Continuous residence" means that you have not left the USA for a long period of time. If you leave the USA for too long, you may interrupt your "continuous residence."

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