Cover: Can the United States Increase Reliance on the Reserves?

Can the United States Increase Reliance on the Reserves?

Published 1994

by Jerry M. Sollinger

Research Brief

Operation Desert Storm highlighted the importance of reserve forces to the U.S. military capability. That importance will be increased by the current drawdown of military forces because the active components are being reduced more than the reserves. But the size of the active force directly influences the readiness of the reserves: People leaving the active force provide an important source of experience for the reserves. Congress, recognizing this connection, has passed legislation that directs sharply increased levels of prior-service personnel in the Army National Guard (ARNG).[1]

However, under current policies, it will be difficult, if not impossible, to increase the prior-service content in the reserves while reducing the size of the active component. A study by RAND's National Defense Research Institute, Prior Service Personnel: A Potential Constraint on Increasing Reliance on Reserve Forces, examines this issue. It analyzes the ratio between active and reserve components, describes the current mix of prior- and non–prior-service personnel in the reserves, projects how the prior-service content would change with different force structures, and presents a menu of policy options designed to boost the prior-service content of the reserves.

Figure 1. Ratio of active to reserve strength by service

Active/Reserve Ratios

Prior-service personnel help the readiness of the reserves because they improve the experience mix and can boost the level of military skills in the unit if they are employed in their prior-service skill. They can also reduce reserve training costs by providing skills for which new reservists would otherwise require training. Figure 1 depicts the ratios between active- and reserve-force sizes. The larger the active component is with respect to the reserve, the larger is the pool of prior-service personnel it generates. A service with a large active element relative to its reserve has a comparative advantage in recruiting experienced personnel. Figure 1 suggests that the Army, with approximately a 1:1 ratio, would have more difficulty filling its reserve ranks with experienced personnel than, say, the Air Force, which has about a 3:1 ratio.

What Is the Current Mix?

Examination of the reserves reveals that prior-service content varies widely across the components. The variation results, in part, from different personnel policies, but the availability of prior-service personnel—driven by the ratios between active and reserve personnel—has a major influence. Figure 2 shows the prior-service content in the six reserve components.

The air components—the Air National Guard (ANG) and the Air Force Reserve (USAFR)—generally have the highest prior-service content. These components are significantly smaller than the active Air Force, so they have a relatively larger personnel pool to draw from. Furthermore, the air components have the lowest attrition of prior-service personnel; thus, they have lower recruiting needs. The Naval Reserve (USNR), also much smaller than its active counterpart, has high prior-service content but a significantly higher loss rate of prior-service personnel. It has the highest loss rate among officers, which means that it is close to being supply-constrained in its recruiting. Like the air and naval reserves, the Marine Corps Reserve (USMCR) is much smaller than the active force. It has a high percentage of officers with prior service but a low level for enlisted personnel as a result of a structure heavy in low-ranking enlisted personnel and an institutional preference for non-prior-service personnel. Officers experience high attrition, and the Marine Corps Reserve is probably close to being constrained by the supply of experienced officers.

Figure 2. Mix of prior-service personnel in FY89

As Figure 2 indicates, with the exception of the USMCR enlisted personnel, the Army's two reserve components (the ARNG and the Army Reserve [USAR]) have the lowest prior-service content of the reserve components. For the National Guard, these levels fall far below current congressional goals.

The Effect of the Drawdown on Prior-Service Content

To determine the effect of the drawdown, the study team used a dynamic model that projects inventories of active-force personnel across a range of force structures. The results indicate that the drawdown will affect the Army the most. Already at nearly a 1:1 ratio, its active-force cuts are proportionately the greatest of any service, and the reserve reductions are smaller than those of the active. The result will be a reserve component 25 percent larger than the active component. For the National Guard and Army Reserve, the study team estimates that prior-service content could dwindle to 23 and less than 50 percent, respectively, for officers and to 20 and 25 percent for the enlisted force. The Air Force undergoes the second-largest reduction, but that reduction should not affect the prior-service content of the air reserves because they are still much smaller than the active force and have queues of people waiting to join. The Navy and Marine Corps take smaller cuts, and their reserve components appear to have queues of enlisted veterans. However, they could suffer modest declines in the percentage of prior-service officers.

The Army could also experience a decline in the level of military skills as a result of decreased availability of prior-service soldiers. Many reservists are not skill-qualified because they are still in training (between 20 and 30 percent prior to Desert Storm). Filling vacancies with trained prior-service soldiers increases the number of positions filled with qualified people, and between 40 and 50 percent of prior-service soldiers find jobs in their skill. Reducing prior-service content could also reduce the level of skill qualification.

Policy Options to Improve Prior-Service Content

The current reductions could signal a historic shift toward dependence on reserves that parallels in magnitude the transition to an all-volunteer force. That transition took 15 years and major changes in personnel and compensation policies. Research helped determine the effectiveness of many of the programs that made the all-volunteer force a reality. The study team suggests a menu of options for testing and evaluating the effect of those options on improving reserve readiness in the post-drawdown era. These options fall into three categories.

Consider Sizing

Take into account the link between active-force size and reserve-force readiness when setting active- and reserve-force sizes. If possible, active and reserve forces should be sized in a way that provides for sufficient transfer of experience from active to reserve forces. In the absence of force-size adjustments, adopt a two-tier readiness posture for high- and low-priority units.

Change Policy to Improve Use of Experienced Personnel Who Join Reserves

Establish proficiency pay to increase the incentive of prior-service personnel to find jobs that use their active-duty skill. Revise the requirements for critical skills to include experience as well as grade and skill levels. Change grade requirements for critical reserve skills to allow progression to higher grades. To get promoted, many reservists leave a job in which they are trained and accept a position that will require them to train in a new skill. Revise policies to encourage better job matching at entry, longevity in jobs, and shorter gaps in service. All these goals would tend to increase the use of experience and improve skill levels.

Increase Experienced Personnel in the Reserves

Expand tests of incentives for active enlistees to accept reserve terms of service. Incentive programs have succeeded on a small scale, but more data are needed to determine how far they can be expanded. Test options for better integrating prior-service personnel in the Individual Ready Reserve as mobilization assets into reserve units to improve readiness and deployability. A final option would be to improve the experience of non-prior-service personnel in the reserves through periods of active service.


  • [1] U.S. House of Representatives, National Defense Authorization Act for Fiscal Year 1993, House Report 102–966 (Washington, D.C.: U.S. Government Printing Office, 1993), directs a prior-service content of 65 percent for officers and 50 percent for enlisted personnel in the Army National Guard.

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