Late application

[agrokosova]

I became a GC holder on June 99 and was eligible to apply on June 04 but did not apply for citizenship yet.
I am planning to apply this month ( 6 years of residency) and I was curious if I have to be physically present in USA 30 months which is the rule for 5yr. residency or 36 months which is half of the time of my 6 year residency.
Also I am curious to know when I fill the trip section of N400 should I include trips that have occured during my last 6th year of my residency or should I include only trips from year 1999 until 2004?