Points & Retirement
You don't need points to retire; you need:
1. 20 total years. That's your active and Reserve/Guard combined.
2. A minimum number of years in the Guard or Reserve. When I became a Reservist, it was 6 years in the Reserve component. I don't know if that has changed or not.
The Importance of Points:
The more points you accumulate, the more money you get at age 60 when you draw your first retirement check (assuming you are not a full-time AGR guy). AGRs get their money immediately after retiring.
Formula:
A 20-year active-duty career is deemed 7200 days of work. Each day is 1 point.
When you retire from the Guard/Reserve, divide your total points by 7200.
That is the fraction of the regular active-duty retirement you will receive.
(BTW, I had 15.5 years when I punched--now have 25+).