The U.S. military’s new Blended Retirement System, which cuts the traditional military pension but provides a personal retirement account that service members can keep even if they don’t serve for a 20-year career, hasn’t seen a lot of signups yet.

The BRS is intended to replace the traditional system. Those who were already serving, but had less than 12 years of service at the time of passage of the 2015 law that launched the BRS, were given a choice of whether to remain in the legacy system or opt for the new. New recruits as of Jan. 1 were enrolled in the BRS.

The traditional system requires 20 years of service to qualify for retirement pay, while the BRS allows service members to put money aside in a Thrift Savings Plan, to which the Defense Department contributes, that is theirs even if they leave the military after a single tour of duty.

But the BRS also cuts the amount of the traditional pension.

So far the rate of opt-ins hasn’t been exactly swift. As of Sept. 30, there are 376,889 total BRS participants—270,069 of whom actually opted in. The remaining 106,820, according to the Pentagon, are new entrants to the military since Jan. 1 who were automatically enrolled.

At present, despite the closeness of the deadline — Dec. 31 — signups are as follows: Army, 85,219 opt-ins out of 810,301 eligible (10.5%); Air Force, 63,234 opt-ins out of 374,003 eligible (16.9%); Navy, 57,262 opt-ins out of 278,910 eligible (20.5%); Marine Corps, 64,354 opt-ins out of 175,627 eligible (36.6%); and total for DOD, 270,069 opt-ins out of the 1,638,841 members who were eligible on Jan. 1 (16.5%).

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