The Congress of the United States O Congressional Budget Office

CBO

Some Implications of Increasing

U.S. Forces in Iraq

April 2007

A

REPORT
Note

Unless otherwise indicated, all years referred to in this paper are calendar years.
Preface

The Administration is currently planning (and has begun to execute) an increase in U.S. 

ground forces in Iraq. That plan calls for increasing the number of U.S. combat brigades intheater by 5 above the December 2006 level of 15, peaking at 20 combat brigades deployed. 

At this time, the Administration has not specified how long it plans to sustain the increase.

This Congressional Budget Office (CBO) paper—prepared at the request of the Chairman of 

the Subcommittee on Defense of the House Committee on Appropriations and the Chairman 

of the House Committee on the Budget—addresses the effects of increasing U.S. forces in 

Iraq on the readiness of U.S. ground forces as well as the effects of not increasing U.S. forces 

or completely withdrawing those forces from Iraq. The paper updates the analyses contained 

in two previous CBO reports on the subject, An Analysis of the U.S. Military’s Ability to Sustain 

an Occupation in Iraq and An Analysis of the U.S. Military’s Ability to Sustain an Occupation in 

Iraq: An Update, to reflect the potential effects of the Administration’s plan to increase U.S. 

forces in Iraq. In keeping with CBO’s mandate to provide impartial analysis, the paper makes 

no recommendations.

Adam Talaber of CBO’s National Security Division prepared this paper under the supervision 

of J. Michael Gilmore and Matthew S. Goldberg. Peter Fontaine, Douglas Hamilton, Arlene 

Holen, Donald Marron, and David Newman reviewed the paper. James Quinliven of the 

RAND Corporation also reviewed the paper. (The assistance of an external reviewer implies 

no responsibility for the final product, which rests solely with CBO.)

Christine Bogusz edited the paper, and John Skeen proofread it. Maureen Costantino 

prepared the paper for publication, Lenny Skutnik printed the initial copies, and Simone 

Thomas produced the electronic version for CBO’s Web site (www.cbo.gov).

Peter R. Orszag

Director

April 2007

Contents

Summary and Introduction 1

Background on the Deployed Force and Mechanics of the Increase 3

Measures of Readiness 5

Rotation Ratios 5

Brigades Immediately Available for Other Contingencies 6

CBO’s Model of Future Deployments 7

The Results of CBO’s Analysis of Five Deployment Scenarios 9

Scenario 1: No Increase in Forces 9

Scenario 2: A Four-Month Increase in Forces 10

Scenario 3: A 12-Month Increase in Forces 11

Scenario 4: A 24-Month Increase in Forces 11

Scenario 5: Withdrawal of Forces 12

Rotation Ratios and Units Immediately Available: An Example 12

Tables

1. Ratio of Units at Home Station to Units Deployed 

Under Alternative Scenarios 2

2. Brigades Immediately Available Under Alternative Scenarios 3

3. Disposition of U.S. Combat Brigades for a Steady 

15-Brigade Occupation of Iraq, Assuming 

12 Months Is Required to Recover from a Deployment 13

4. Disposition of U.S. Combat Brigades for a Steady 

15-Brigade Occupation of Iraq, Assuming 

6 Months Is Required to Recover from a Deployment 14
VI SOME IMPLICATIONS OF INCREASING U.S. FORCES IN IRAQ

Figures

1. Rotation Ratios Under Alternative Scenarios 9

2. Units Available for Other Contingencies at 6 Months’ 

Recovery Under Alternative Scenarios 10

3. Units Available for Other Contingencies at 

12 Months’ Recovery Under Alternative Scenarios 11
Some Implications of

Increasing U.S. Forces in Iraq

Summary and Introduction

The Administration is currently planning (and has begun 

to execute) an increase in U.S. ground forces in Iraq. 

That plan calls for increasing the number of U.S. combat 

brigades in-theater by 5 above the December 2006 level 

of 15, peaking at 20 combat brigades deployed. At this 

time, the Administration has not specified how long it 

plans to sustain such an increase.

This Congressional Budget Office (CBO) analysis considers the effects of increasing U.S. ground forces in Iraq. 

In particular, it analyzes the effects on operational tempo 

and availability of units to respond to other contingencies. To analyze those effects and compare them with the 

alternatives for employing U.S. forces incorporated in the 

House and Senate versions of the supplemental appropriation for fiscal year 2007, CBO constructed five deployment scenarios.

B Scenario 1: U.S. force levels return to and are then 

maintained indefinitely at 15 combat brigades intheater (that is, no increase in forces beyond what has 

already been executed);

B Scenario 2: A 4-month increase that builds up to 20 

combat brigades in-theater by May 2007 and sustains 

that increase until August 2007;

B Scenario 3: A 12-month increase that builds up to 20 

combat brigades in-theater by May 2007 and sustains 

that increase until April 2008;

B Scenario 4: A 24-month increase that builds up to 20 

combat brigades in-theater by May 2007 and sustains 

that increase until April 2009; and

B Scenario 5: A withdrawal from Iraq that steadily 

reduces the number of combat brigades in-theater 

from current levels until all U.S. combat brigades have 

departed by June 2008.

This analysis updates CBO’s previous work on this topic, 

An Analysis of the U.S. Military’s Ability to Sustain an 

Occupation in Iraq (September 2003) and An Analysis 

of the U.S. Military’s Ability to Sustain an Occupation in 

Iraq: An Update (October 2005), using the same measures of stress on the force (rotation ratios and number of 

brigades immediately available to respond to other contingencies).

In the scenarios considered by CBO, the increase in 

forces in Iraq would, as long as it was sustained, increase 

the pace of deployments for U.S. active-component 

ground forces. U.S. forces are generally rotated through 

Iraq and Afghanistan as units (not as individual personnel) according to a “deploy, recover, prepare” cycle. When 

units are required to deploy more often, they are able to 

spend less of their time recovering from a deployment 

and preparing at home station for the next deployment 

compared with the time they spend deployed. The 

Army’s goal for its active-component combat forces is to 

maintain at least two units at home station (one recovering and one preparing) for every unit deployed. The 

Army indicates that this level of operational tempo would 

be consistent with maintaining a ready force.

Depending on how long it was sustained, the increase in 

forces in Iraq would cause the ratio of the number of 

units at home station to every unit deployed to decline 

from its current level of about 1.2 to approximately 0.9, 

in CBO’s estimation (see Table 1). That change would 

be an increase of about 30 percent in the rate at which 

U.S. active-component ground forces were deployed 
2 SOME IMPLICATIONS OF INCREASING U.S. FORCES IN IRAQ

Table 1.

Ratio of Units at Home Station to Units Deployed Under Alternative Scenarios

Source: Congressional Budget Office.

compared with maintaining U.S. forces in Iraq at their 

December 2006 level, and it would have U.S. forces 

spending more time deployed than at home station. After 

the increase in forces ended, the operational tempo of 

U.S. active-component ground forces would eventually 

recover to about 1.8 units at home station for every unit 

deployed.1

The increase in forces in Iraq also would decrease the 

number of U.S. combat brigades immediately available to 

respond to other contingencies (see Table 2). In CBO’s 

analysis, that decrease would continue for at least six 

months after U.S. forces began to draw down until those 

units that were deployed had sufficient time at home station to recover from their deployments. After the temporary increase ended, the number of combat brigades 

immediately available to respond to other contingencies 

would eventually recover to about 18 to 25. There would, 

however, be a lag in time before those numbers were 

achieved—CBO’s analysis indicates that, absent a withdrawal, by December 2009 at most 13 to 21 brigades 

would be immediately available to respond to another crisis. The Department of Defense’s (DoD’s) planning in 

the past for executing a major theater war (such as the 

defense of the Republic of Korea) incorporated five Army 

divisions, one Marine Corps division, and two armored 

cavalry regiments—the equivalent, at that time, of 20 to 

21 combat brigades. Smaller operations, such as Operation Enduring Freedom (in Afghanistan) or Operation 

Uphold Democracy (in Haiti), are often conducted with 

two to four brigades.

If the increase in forces is sustained into the fall of 2007, 

deployment tours longer than 12 months for active 

Army deployments become necessary to provide 

12 months of “dwell time” (time spent recovering from a 

deployment) at home station. When rotation rates fall 

below one unit at home station for every unit deployed, 

units have less than 12 months at home station to prepare 

for their next 12-month deployment. Secretary of 

Defense Robert M. Gates has committed DoD to providing at least 12 months of dwell time for all units. CBO’s 

scenarios with 12-month and 24-month increases in 

forces were modeled using 15-month tours for Army 

active combat units (consistent with Secretary Gates’ 

announcement on April 11, 2007, which stated that such 

deployments would allow DoD to maintain the increase 

in forces for at least a year). The other cases were modeled 

using 12-month tours for active Army combat units. 

That increase in forces, although larger than the previously planned level of 15 combat brigades in Iraq, would 

be comparable to the level of U.S. ground combat forces 

in Iraq in the summer and fall of 2003 as well as for the 

winters of 2004 and 2005 and 2005 and 2006. However, 

none of those levels was sustained for as long as the 12-

month or 24-month increases that CBO considered.

The pool of forces that the United States has available to 

sustain 15 or 20 brigades in Iraq is 50 active-component 

Army and Marine Corps combat brigades (rising to 52 by 

the end of the time period CBO considered) and 37 

reserve-component combat brigades (declining to 31 by 

the end of the time period CBO considered). In addition 

to deployments to Iraq, that pool must also sustain forces

Scenario

No Increase in Forces 1.2 1.6 1.8

4-Month Increase in Forces 1.0 1.5 1.8

12-Month Increase in Forces 0.9 1.2 1.7

24-Month Increase in Forces 1.0 1.0 1.4

Withdrawal of Forces 1.3 4.6 7.7

Memorandum:

Army's Goal 2.0 2.0 2.0

December 2007 December 2008 December 2009 

1. The operational tempo of active-component combat forces in 

CBO’s model recovers from the current 1.2 units at home station 

for every unit deployed to the higher level of 1.8 units because of a 

number of factors, including the relatively limited use of National 

Guard brigades in 2006, an increased supply of modular brigades, 

and a lower number of forces deployed.
SOME IMPLICATIONS OF INCREASING U.S. FORCES IN IRAQ 3

Table 2.

Brigades Immediately Available Under Alternative Scenarios

Source: Congressional Budget Office.

Note: Because it is unclear how long units require to recover from a deployment, CBO modeled a range of possible recovery times—6 and 12 

months—to illustrate the range of possible effects.

deployed to Afghanistan (normally, three brigades), in 

Marine expeditionary units (MEUs), and stationed in 

Korea and Okinawa.2

In all of the cases that CBO considered, the actual effect 

that the increase in forces in Iraq will have on deployment 

rates and the availability of units for other contingencies, 

as well as the specific details of the how the increase will 

affect both active- and reserve-component Army and 

Marine Corps units, depends on the details of how the 

increase is executed. At this time, DoD has not publicly 

released a full schedule of proposed deployments, nor has 

it committed to a specific length of time to sustain the 

increase in forces. CBO has compiled publicly available 

data on deployment dates for all active- and reservecomponent Army combat brigades and Marine Corps 

infantry battalions and constructed plausible future 

deployment scenarios. Although it is unlikely that those 

scenarios will precisely match DoD’s future announcements, they serve to illustrate the effects of various policy 

choices.

In the case of a withdrawal from Iraq, the only major 

deployments that U.S. ground combat forces would need 

to sustain would be forces in Afghanistan and MEUs. 

Thus, the operational tempo of active-component 

ground combat forces would be reduced, ultimately leading to about 14 units at home station for every unit 

deployed. The operational tempo of reserve-component 

ground combat forces would also be reduced, ultimately 

leading to about 24 units at home station for every unit 

deployed. In addition, a withdrawal of forces from Iraq 

would eventually increase the number of combat brigades 

available to respond to other contingencies to more than 

40.

Background on the Deployed

Force and Mechanics of the Increase

U.S. forces in the Iraq theater of operation include personnel deployed to both Iraq proper and to neighboring 

countries (particularly Kuwait). Prior to the announcement of the increase in forces in Iraq, those forces 

included about 20,000 Air Force personnel, 25,000 

Marine Corps personnel (with two regiments deployed), 

and 120,000 Army personnel (with 13 to 14 brigades 

deployed).

Not all of those personnel are in ground combat units. 

An Army combat brigade, depending on its type, will 

have between 3,400 and 3,800 personnel normally 

assigned to it (although it is common practice for the 

Army to assign more personnel to a unit deploying to a 

combat zone—in that case, personnel fill rates of 105 to 

110 percent are normal). The remaining military personnel in-theater are associated with various units that command or support the combat brigades (for example, the 

Scenario

No Increase in Forces 5 6 13 13 16 21

4-Month Increase in Forces 4 4 12 11 14 21

12-Month Increase in Forces 4 3 9 11 11 19

24-Month Increase in Forces 4 2 8 12 10 17

Withdrawal of Forces 6 16 33 14 26 38

Memorandum:

Forces for One Major Theater War 20 20 20 20 20 20

Recover from Deployments

Assuming 12 Months Is Required to Assuming 6 Months Is Required to 

Dec. 2008 Dec. 2009

Recover from Deployments

Dec. 2007 Dec. 2008 Dec. 2009 Dec. 2007

2. MEUs are the Marine Corps forces embarked upon expeditionary 

strike groups (ESGs, formerly amphibious strike groups). Normally, the core of each MEU is a Marine infantry battalion, and 

there are four MEUs deployed.
4 SOME IMPLICATIONS OF INCREASING U.S. FORCES IN IRAQ

corps headquarters, logistics commands, medical evacuation units, engineers, and so forth) The majority of those 

personnel perform functions that directly support combat brigades, and their number varies in proportion to the 

number of combat brigades in-theater.3

 Marine Corps 

regiments are similar in that respect.4

Almost all of the U.S. forces in the Iraq theater are 

deployed there on a rotational basis. That arrangement 

means that units deploy, along with all of their personnel 

and most of their equipment, for a finite time and then 

leave the theater (generally, being replaced by another 

similar unit).5 Army units have typically deployed for 12 

months, while Marine Corps units have deployed for 7 

months. That schedule allows U.S. forces to return to 

their home stations to replace personnel and equipment, 

conduct training activities, and generally recover from the 

stresses of deployments. To date, DoD has attempted to 

deploy most ground combat units for no more than one 

year to the Iraq theater and has attempted to ensure that 

units receive at least one year at home station before they 

are deployed to Iraq again. That practice, which means 

that only a fraction of U.S. forces are deployed at any 

one time, improves readiness and quality of life for U.S. 

forces.

Prior to the announcement of the Administration’s plan 

to increase the size of the force in Iraq, DoD had been 

assuming that the 2007 rotation of forces to Iraq would 

remain stable at about 15 brigades.6

 DoD does not 

announce predicted force levels for more than 6 to 12 

months in the future because conditions in Iraq (and, 

therefore, the demand for forces) may change over time. 

However, most descriptions of the increase in forces have 

implicitly assumed that once the period of the increase to 

20 brigades is over, U.S. forces in Iraq will return to some 

lower level (such as the prior 15-brigade commitment).

The Administration plans to execute the increase in 

forces in Iraq largely by extending the tours of some units 

currently in Iraq and accelerating the deployment of 

other units already scheduled to deploy there. Therefore, 

the increase will largely not involve “new” units that were 

not previously scheduled to deploy to Iraq. For example, 

by extending the deployment of the 1st Brigade, 34th

Infantry Division until August 2007, that brigade will be 

in Iraq in July 2007, increasing the number of U.S. brigades in Iraq in that month by one compared with a scenario in which the 1st Brigade, 34th Infantry Division 

had redeployed to its home station in the spring of 2007. 

Secretary Gates announced on April 11, 2007, that all 

active-component Army combat brigades in Iraq would 

have their deployments extended to 15 months (whereas 

previously, most had been scheduled for 12-month 

deployments). Extending the tours of all activecomponent Army units currently in the theater would 

allow DoD to sustain the increase for about a full year.

In general, regardless of whether U.S. forces in Iraq are 

increased by deploying units more frequently (accelerating unit deployments, deploying additional units) or by 

deploying units for longer periods of time (extending 

deployments), the force will experience comparable levels 

of increased operational tempo (though that increase may 

not be distributed equally across all units). Units will 

experience, on average, a reduction in the amount of time 

they spend at home station compared with the amount of 

time they are deployed, and fewer units will be immediately available that are not already deployed or recovering 

from a deployment.

DoD’s policy of providing at least one year of dwell time 

for all units to recover from a deployment requires tours 

in Iraq or Afghanistan longer than 12 months when the 

number of units deployed exceeds the number of units at 

home station. A 15-month tour for deployed units (as 

DoD has announced) will allow the forces to operate at 

ratios as low as 0.8 units at home station for every unit 

deployed while still allowing 12 months of dwell time for 

all units.

The increase in forces in Iraq may not lead to a higher 

operational tempo for the Army National Guard’s com3. See Congressional Budget Office, Estimated Costs of Increasing 

U.S. Forces in Iraq (letter to the Honorable John M. Spratt, Jr., 

February 1, 2007).

4. Marine Corps regiments are similar in size and capability to Army 

brigades. In this analysis, when CBO is discussing the overall U.S. 

ground combat force deployed to Iraq, CBO counts regiments as 

brigades.

5. The Army currently maintains a pool of equipment in the Iraq 

theater that is provided to units deploying there and retained intheater when they redeploy out of the theater. In other rotations, 

units rotate with all of their equipment.

6. Department of Defense, “Adjustments to Iraq Troop-Rotation 

Schedules Announced Yesterday Will Allow 15 U.S. Combat Brigades to Be in Iraq Through Spring, DoD Officials Said Today” 

(press release, September 2006), available at www.defenselink.mil/

news/newsarticle.aspx?id=1220.
SOME IMPLICATIONS OF INCREASING U.S. FORCES IN IRAQ 5

bat brigades unless it is sustained for a lengthy period. 

The Army employed the National Guard at a high rate 

during the 2004–2005 period, which, in combination 

with DoD’s guidelines for the employment of the reserve 

component, leaves the Army with relatively few available 

Army National Guard combat brigades during the 2007–

2008 period. That could change if DoD chose not to 

adhere to the goals in its recently announced policy on 

the employment of reserve-component combat units.7

 In 

addition, the 2007–2008 period is one in which many 

National Guard combat brigades are scheduled for conversion to the modular configuration, meaning that they 

would not be available for employment unless the Army 

changed its plans for those conversions.8

It is unlikely that the recently announced decision to 

enlarge the size of the Army and Marine Corps, including 

the creation of six active Army combat brigades and one 

Marine Corps regiment, will affect the available U.S. 

forces significantly during the time of the increase in U.S. 

forces in Iraq. The bulk of the funding for the newly created brigades is provided beginning in fiscal year 2008, 

and recruiting additional personnel and establishing new 

units will require at least two years beyond that. Thus, 

most of the additional combat units will not be available 

in time to participate in the increase in forces in Iraq during the periods spanned by the cases CBO considered—

only one additional Army brigade and the additional 

Marine Corps regiment should be available by the end of 

the time period CBO considered.

Measures of Readiness

CBO was asked to analyze the effects of the temporary 

increase on the readiness of U.S. ground forces. DoD has 

traditionally measured and presented readiness in the 

form of Status of Resources and Training System 

(SORTS) scores, ranging from C-1 (fully ready) to C-4 

(not ready), with C-5 used for units undergoing reorganization.9

 Because CBO has no way to analyze and definitively predict the effects of deployments of various 

lengths on SORTS scores, it chose two other measures of 

readiness. 

Rotation Ratios 

CBO used rotation ratios as a way of examining stress on 

the overall force. Rotation ratios—the number of units at 

home station for every unit deployed—can be generated 

from publicly available information, can be consistently 

modeled, and can be compared with public statements 

made by DoD and service leadership. Longer deployments and shorter recovery times (that is, lower rotation 

ratios) are clearly associated with greater wear on equipment and less time at home station for necessary training—implying lesser readiness. Because rotation ratios 

can be translated into dwell-time measurements relatively 

easily, they can also be compared against simple benchmarks such as “every unit should have at least one year of 

time at home station between deployments” or “units will 

be deployed no more than one year out of every six.” 

Similarly, a rotation ratio of less than one implies that 

units are spending more time deployed than at home 

station. To the extent that the occupation of Iraq (along 

with other deployments) requires that forces be employed 

more frequently than what is stated in those goals, the 

force is under more stress than DoD or the services would 

desire.

7. DoD’s most recent policy on employing reserve-component units 

is that units will be mobilized for no more than one year out 

of every six. Similarly, the Army’s goal for use of its reservecomponent combat units is one year mobilized out of every six for 

“steady-state” conditions and one year out of every five for “surge” 

conditions. Under those guidelines, National Guard combat brigades mobilized within the past four to five years are not eligible 

for remobilization. Even under the more relaxed “surge” condition 

standard, that policy allows only National Guard brigades that 

have not been mobilized since 2003 to be used in the 2007–2008 

time frame, leaving many units ineligible for deployment.

8. DoD has notified four Army National Guard combat brigades 

that they may be deployed as soon as December 2008. Some of 

those brigades have previously been deployed within the time 

period that DoD’s new policy would appear to prohibit. See 

www.defenselink.mil/releases/release.aspx?releaseid=10711.

9. SORTS is used to provide the readiness data in DoD’s major 

readiness reporting format to Congress, the Quarterly Readiness 

Report. A unit’s C-rating in SORTS is based on lower-level ratings 

measuring how many of the unit’s assigned personnel (P-level) 

and equipment (S-level) it possesses, the condition of that equipment (R-level), and how well trained the unit is (T-level), modified by the unit commander’s subjective judgment of the unit’s 

readiness. 
6 SOME IMPLICATIONS OF INCREASING U.S. FORCES IN IRAQ

The DoD leadership has stated goals for operational 

tempo in terms of rotation ratios.10 The Army’s Force 

Generation Model, the service’s current approach for 

managing deployments to Iraq and Afghanistan, is 

intended to establish a rotation ratio of two units at home 

station for every unit deployed. That model is based on 

units going through a “deploy, recover, prepare” cyclical 

readiness construct, similar to what Marine Corps and 

Navy units have historically used. In the model, during 

the period of increased demand for forces occasioned by 

the occupation of Iraq (the model’s surge phase), active 

Army combat units would deploy for one year, recover for 

one year, and prepare for their next deployment for one 

year. That approach would leave one-third of the force 

deployed at any one time, one-third of the force available 

to respond to other contingencies, and one-third of the 

force recovering from deployments (and would be functionally identical to the measures used by CBO with a 2.0 

rotation ratio, 12-month deployments, and 12 months 

for units to recover from deployments—the remaining 

units would be available to respond to other contingencies for 12 months). After the end of the occupation of 

Iraq, the model calls for twice as many active Army combat units to be preparing for deployment as are either 

deployed or recovering from a deployment (the model’s 

steady-state phase).11 That arrangement would leave onequarter of the force deployed at any one time, one-half of 

the force available to respond to other contingencies, and 

one-quarter of the force recovering from deployments 

(and would be identical to the measures used by CBO, 

except with a 3.0 rotation ratio).

In addition, DoD’s most recent revisions to its reservecomponent employment policy (units mobilized no more 

than one year out of every six) imply a desired rotation 

ratio for reserve-component units of about seven units at 

home station for every unit deployed.12 The Army’s 

Force Generation Model calls for a National Guard combat unit to be mobilized one year out of every five under 

surge conditions and one year out of every six under 

steady-state conditions. 

Brigades Immediately Available for

Other Contingencies 

The United States maintains forces deployed to a number 

of locations and is frequently concerned with a wide 

range of potential contingencies that might arise unexpectedly. It is possible to model how many units would be 

immediately available for other contingencies in a fairly 

direct fashion, given assumptions about how long after a 

deployment a unit needs to recover. It is not clear from 

the readiness data available to CBO how long units 

require to recover from a deployment. In addition, the 

United States does not have extensive historical experience with rotating large numbers of Army units at current rates over extended periods, so there is no historical 

analogy that can be used. Because of that uncertainty, 

CBO showed a range for how many units would be available to respond to other contingencies. The specific 

recovery times used to generate that range are bracketed 

on the high end by the one year of dwell time that the 

Army and DoD have repeatedly stated they strive to provide all units before redeploying them. At the low end, it

10. Between 2002 and 2003, DoD changed the way it measures rotation ratios. Previously, those ratios referred to the total number of 

units in the force for every unit deployed. The previous definition 

was exactly equivalent to the new definition plus one (in the new 

formulation, the deployed unit itself is not counted). CBO’s previous work on the sustainability of the occupation in Iraq used the 

old definition; however, this analysis adopts the new definition.

11. The terms “steady state” and “surge” are the Army’s. In this context, surge does not refer (as it does in press accounts) to the proposed increase in forces in Iraq. Instead, it refers to the first phase 

of the implementation of the Army’s Force Generation Model. 

That first phase appears to be roughly equivalent to the duration 

of the occupation of Iraq, for however long the occupation is 

maintained.

12. DoD’s goals for rotation ratios for active- and reserve-component 

units differ in an important way. Goals for active-component 

units are based on deployed versus nondeployed time, whereas 

goals for reserve-component units are based on mobilized versus 

nonmobilized time. Because reserve-component units require 

some time while mobilized to train, deploy, and redeploy, the 

effective rotation ratio for deploying reserve-component units will 

be lower than the rotation ratio for mobilizing reserve-component 

units. One of the Army’s goals is to reduce the amount of time its 

National Guard brigades require in a mobilized but not deployed 

status, by improving premobilization training activities. See 

Department of Defense, “DoD Announces Changes to Reserve 

Component Force Management Policy” (press release, January 

2007), available at www.defenselink.mil/releases/release.aspx? 

releaseid=10389. 
SOME IMPLICATIONS OF INCREASING U.S. FORCES IN IRAQ 7

is not clear how fast a unit might recover, so CBO used a 

six-month recovery time to illustrate the sensitivity of this 

metric to the assumptions used.13

The range of recovery times also illustrates an important 

element of any U.S. response to a potential contingency. 

Presumably, in any other contingency, DoD would 

deploy first its most ready forces (those that had recovered most fully from a deployment), with less ready forces 

deployed later and as needed. In such a response, it is possible to think of the different numbers of brigades immediately available for other missions as illustrating the 

numbers of forces available for contingencies of different 

priorities. For a low-priority mission, one for which DoD 

was unwilling to accept much risk, it would perhaps only 

employ fully recovered brigades with 12 months since 

their last deployment. However, for a high-priority 

mission, which DoD considered urgent, it would perhaps 

be willing to employ brigades with only 6 months (or 

even less) since their last deployment; that is, for an 

important enough mission, DoD might be willing to 

employ less ready units. Hence, the pool of units immediately available could increase with respect to higher priority contingencies.

This measure reflects only the units immediately available 

for deployment. Over a sufficient period of time, for a 

contingency that national policymakers considered 

important enough, effectively all U.S. ground forces 

could be deployed. In the time period CBO analyzed, 

that would include 43 active Army and 28 National 

Guard brigades, 9 active and 3 Marine Corps Reserve regiments, for 83 brigades total. Given sufficient time, units 

currently recovering from deployments could be made 

ready (and, with a sufficiently important contingency, 

that might be a very short period of time), National 

Guard brigades and Marine Corps Reserve regiments 

could be mobilized and trained, and in extreme cases, 

units could be withdrawn from contingencies in other 

theaters.

As such, the number of ground forces the United States 

would have available to respond to another contingency 

is always sensitive to the national importance of the other 

contingency and the time period in which a response is 

required. Although 20 brigades is an appropriate amount 

of forces to assume would be required for a major contingency (such as, for example, the defense of the Republic 

of Korea), it is possible that the United States could still 

prevail in any such contingency in cases in which it 

would have fewer than 20 brigades immediately available. 

Although the U.S. response might be more difficult or 

slower than ideal, it would always be possible, given sufficient time, to send additional forces to such an operation.

CBO’s Model of Future Deployments

To analyze the increase in forces in Iraq, CBO constructed a model of how U.S. ground combat forces have 

been and would be deployed. That model tracks the status of all active- and reserve-component Army and 

Marine Corps combat units by month, detailing which 

units are deployed to Iraq, Afghanistan, Marine expeditionary units, or other assignments; which units are 

deploying or redeploying; which units are being converted to Stryker brigades or modular brigades; when new 

active Army combat brigades have been or are planned to 

be established; and the time each unit has had at home 

station since its last deployment. For estimating deployments in the future, the model assumes that units would 

be deployed on the basis of how long they have had since 

their last deployment, with units that have had longer to 

recover being deployed first. Deployments are scheduled 

so as to maintain the levels of forces specified for each scenario that CBO considered.

Except for the withdrawal case, CBO’s model assumes 

that U.S. forces in Iraq will be maintained indefinitely at 

the level of 15 combat brigades after the end of any given 

temporary increase. That level is usually composed of two 

Marine Corps regiments, two to three Army National 

Guard brigades, and 10 to 11 active Army brigades. It 

also assumes that U.S. forces in Afghanistan will be maintained indefinitely at the level of three combat brigades 

beyond 2007, usually composed of one Army National 

Guard brigade and two active Army brigades. In addition, it assumes that the Marine Corps continues to 

deploy Marine expeditionary units, maintains forces in 

Okinawa, and builds to 9 active regiments by 2008 and 

that the Army maintains the 1st Brigade, 2nd Infantry 

Division, in Korea, restructures 6 National Guard com13. Arguably, units could recover extremely rapidly if unit commanders were aware of time pressure. Less essential training exercises 

could be canceled, equipment could be retained in the unit 

instead of being sent to depots for scheduled maintenance, personnel could be retained in the unit instead of being reassigned, 

and so on. However, most of those measures would require 

advance knowledge that the unit would be needed on short 

notice. An unexpected contingency (the most common kind) 

would not permit any of those countermeasures to be employed in 

advance.
8 SOME IMPLICATIONS OF INCREASING U.S. FORCES IN IRAQ

bat brigades by 2009, and builds to 43 active combat brigades by 2009.14 This model provides CBO’s analytic 

results for what the effects of any given deployment pattern are on the operational tempo of active- and reservecomponent ground combat forces as well as the number 

of brigades that would be available to respond to another 

contingency.

CBO measured operational tempo using rotation ratios. 

Those ratios can be converted to the common alternative 

metric of dwell time roughly by multiplying them by 12 

months (assuming 1-year deployments). Hence, a rotation ratio of 2:1 (or 2.0), with two units at home station 

for every unit deployed (the Army’s goal for its activecomponent brigades), and with 1-year deployments, 

means a 24-month dwell time. In CBO’s model, rotation 

ratios are averages of the ratio over the past 12 months, so 

the rotation ratio in December 2007 provides the average 

rotation for calendar year 2007.15 Those ratios are calculated by dividing the supply of available combat units 

(the entire force minus units dedicated to Korea) by the 

demand for units (all units that are deployed, deploying, 

or redeploying). Active- and reserve-component rotation 

ratios are tracked separately.

Another readiness metric is the number of brigades that 

would be available to immediately respond to another 

contingency, should they be needed. It excludes all units 

that are currently deployed (except for MEUs); units that 

are deploying, redeploying, or converting to Stryker or 

modular configuration; and units that have returned 

from a previous deployment in the past 6 or 12 months 

(depending on the assumptions made about how long 

units require to recover from a deployment).16 It excludes 

all National Guard brigades because they usually require 

some time for mobilization and training before they can 

be deployed and are thus not immediately available. 

Those values are also averaged over the previous 12 

months.

For comparison, DoD’s planning in the 1990s assumed 

that five Army divisions, one Marine Corps division, and 

two armored cavalry regiments—the equivalent, at that 

time, of 20 to 21 combat brigades—would be necessary 

to prosecute a major theater war. The initial phase of 

Operation Iraqi Freedom was conducted with only 10 

U.S. brigades; however, many other forces (such as the 

4th Infantry Division and 3rd Armored Cavalry Regiment) were still being deployed. Once all of those forces 

had arrived in-theater (by May 2003), the total size of the 

force deployed for Operation Iraqi Freedom was also 

about 20 brigades. Smaller operations, such as Operation 

Enduring Freedom (in Afghanistan), or Operation 

Uphold Democracy (in Haiti), are frequently conducted 

with as few as two to four combat brigades.

CBO’s model has some limitations. CBO constructed its 

model using publicly available information, including 

non-DoD sources, which may not be completely accurate. DoD has not, to date, provided CBO with detailed 

information about either past deployments of U.S. forces 

or planned future deployments. Because of those data 

limitations, the model tracks forces over time at the level 

of brigades and months. For some cases—such as precisely describing deployments of Marine Corps forces, 

tracking exact force levels during the annual rotation of 

forces, or tracking the exact amount of time consumed by 

deployment and redeployment—that level of aggregation 

can provide only approximations.

CBO’s model is also sensitive to certain assumptions. For 

example, the rotation ratios generated by the model that 

measure operational tempo are affected by decisions 

CBO made about how heavily to emphasize active- or 

14. For reference, prior to the decision to expand the size of the Army 

by 6 active-component brigades, the Army had a planned strength 

of 42 active brigades, with a future decision as to whether it would 

establish a 43rd brigade. The decision by the Administration in 

January 2007 to increase the size of the Army has rendered the 

Army’s decision moot (since the Army will grow to 48 brigades), 

but 1 new brigade is available relatively rapidly compared with the 

other 5, as the Army had already planned for a 43rd brigade. 

CBO’s model assumes that new brigade will be available at the 

beginning of fiscal year 2009.

15. It is necessary to average rotation ratios over a significant period of 

time to provide a meaningful measure of the broader effects of 

changes in the size of the deployed force. Any rotation ratio calculated for a time period of less than a year will be highly sensitive to 

such short-term phenomena as the annual rotation of forces.

16. CBO’s previous work on the sustainability of the occupation 

assumed that units with 12 months or less of time since returning 

from their last deployment would be unavailable to immediately 

respond to other contingencies. See Congressional Budget Office, 

An Analysis of the U.S. Military’s Ability to Sustain an Occupation in 

Iraq (September 2003), available at www.cbo.gov/showdoc.cfm? 

index=4515&sequence=0. This analysis relaxes that assumption; 

however, DoD policy requires 12 months of dwell time for units 

at home station before deploying them again, so the 12-month 

recovery cycle best approximates actual DoD practice.
SOME IMPLICATIONS OF INCREASING U.S. FORCES IN IRAQ 9

Figure 1.

Rotation Ratios Under Alternative Scenarios

(Ratio of units at home station to units deployed)

Source: Congressional Budget Office.

reserve-component participation in future deployments 

to Iraq. In addition, the number of units immediately 

available for other contingencies derived from CBO’s 

model depends on assumptions about how long units 

might require to recover from a deployment (in this analysis, 6 or 12 months).

The Results of CBO’s Analysis of Five 

Deployment Scenarios

CBO derived rotation ratios for the five deployment scenarios it considered in this analysis (see Figure 1). Except 

for the scenario of troop withdrawal, all of the scenarios 

show lower rotation ratios than the Army’s stated goal of 

2.0. Historically, the path of operational tempo reached a 

sharp low in early 2004 (when essentially every activecomponent unit in the Army had deployed for Operation 

Iraqi Freedom or replaced a unit that had deployed), 

recovered through 2005 (when the Army made very 

extensive use of National Guard combat forces), and 

slowly declined through 2006 (when the Army made 

much more sparing use of National Guard combat forces 

and was still creating new modular brigades).

The number of brigades immediately available to respond 

to other contingencies varies in each scenario (see 

Figure 2). Those calculations assume that units require 

6 months to recover after a deployment; the number of 

available brigades declines under the alternative assumption that units require 12 months to recover after a 

deployment (see Figure 3). For all scenarios, CBO 

assumed that a 20-brigade level of forces would be necessary to conduct a major theater war. DoD policy requires 

units to have at least 12 months of time to recover from a 

deployment before being deployed again; as such, 

Figure 3 presents the number of brigades immediately 

available that is most consistent with DoD’s current 

practice.

Scenario 1: No Increase in Forces 

In this case, the operational tempo of U.S. activecomponent ground combat forces recovers from the stress 

of the 2006 deployment and stabilizes at a rate of 1.8 

units at home station for every unit deployed (see 

Figure 1). The scenario maintains 12-month deployment 

tours for active-component Army combat forces. The 

recovery is largely due to the availability of Army 

Jan.

2004

Jul.

2004

Jan.

2005

Jul.

2005

Jan.

2006

Jul.

2006

Jan.

2007

Jul.

2007

Jan.

2008

Jul.

2008

Jan.

2009

Jul.

2009

0.0

0.5

1.0

1.5

2.0

2.5

No Increase in Forces

4-Month Increase in Forces

12-Month Increase in Forces

24-Month Increase in Forces

Withdrawal of Forces

Goal

Army's Rotation Ratio Goal

0
10 SOME IMPLICATIONS OF INCREASING U.S. FORCES IN IRAQ

Figure 2.

Units Available for Other Contingencies at 6 Months’ Recovery 

Under Alternative Scenarios

(Brigades immediately available to respond)

Source: Congressional Budget Office.

modular and Stryker brigades. The number of combat 

brigades immediately available to respond to other contingencies steadily increases from between 4.8 and 9.8 

brigades in April 2007 (assuming 12 or 6 months of 

recovery time) to between 12.5 and 21.1 at the end of 

calendar year 2009 (see Figures 2 and 3).17 In this case, 

the Army National Guard’s combat brigades stabilize at 

about 7 units at home station for every unit deployed. It 

should be noted that this case does not strictly have 15 

brigades in Iraq indefinitely because some units that will 

constitute the increase have already been deployed to 

Iraq. However, in this case, those units are not further 

reinforced, and unit extensions (such as the extension of 

the 1st Brigade, 34th Infantry Division) are reversed, leading U.S. force levels in Iraq to return to 15 brigades by 

July 2007.

Scenario 2: A Four-Month Increase in Forces 

In this case, with U.S. forces in Iraq increasing to 20 brigades by May 2007 and remaining at that level through 

August 2007, the operational tempo of U.S. activecomponent ground combat forces increases—and the 

corresponding rotation ratio decreases—to a low of 1 

unit at home station for every unit deployed (in October 

2007). As operational tempo subsequently declines, the 

rotation ratio increases toward the stable level of 1.8 units 

at home station about 6 months later than is the case in 

Scenario 1 (see Figure 1). It is possible to execute this 

increase while still maintaining 12-month deployment 

tours for active-component Army combat forces. The 

number of combat brigades immediately available to 

respond to other contingencies drops to a low of between 

3.8 and 11.2 brigades in November 2007 (assuming 12 

or 6 months of recovery time) before rising toward 

between 11.6 and 20.5 at the end of calendar year 2009 

(see Figures 2 and 3). In this case, the Army National 

Guard’s combat brigades stabilize at about 7 units at 

home station for every unit deployed.

Jan.

2004

Jul.

2004

Jan.

2005

Jul.

2005

Jan.

2006

Jul.

2006

Jan.

2007

Jul.

2007

Jan.

2008

Jul.

2008

Jan.

2009

Jul.

2009

0

5

10

15

20

25

No Increase in Forces

4-Month Increase in Forces

12-Month Increase in Forces

24-Month Increase in Forces

Withdrawal of Forces

Goal

Forces for One Major Theater War

17. In this case, as in all of CBO’s modeled deployment scenarios, 

fractional numbers of brigades immediately available are a result 

of averaging over 12 months.
SOME IMPLICATIONS OF INCREASING U.S. FORCES IN IRAQ 11

Figure 3.

Units Available for Other Contingencies at 12 Months’ Recovery

Under Alternative Scenarios

(Brigades immediately available to respond)

Source: Congressional Budget Office.

Scenario 3: A 12-Month Increase in Forces

In this case, with U.S. forces in Iraq increasing to 20 brigades by May 2007 and remaining at that level through 

April 2008, the operational tempo of U.S. activecomponent ground combat forces increases—and the 

corresponding rotation ratio decreases—to a low of 0.9 

units at home station for every unit deployed (from 

December 2007 through July 2008). Thereafter, operational tempo declines and the rotation ratio increases 

toward the stable level of 1.8 units at home station (see 

Figure 1). This case would require increasing the length 

of deployments to 15-month tours for active-component 

Army forces. The number of combat brigades immediately available to respond to other contingencies drops to 

a low of between 2.7 and 11.3 brigades in December 

2008 (assuming 12 or 6 months of recovery time) before 

rising toward between 8.8 and 19.4 at the end of calendar 

year 2009 (see Figures 2 and 3). In this case, the Army 

National Guard’s combat brigades stabilize at about 7 

units at home station for every unit deployed.

Scenario 4: A 24-Month Increase in Forces

In this case, with U.S. forces in Iraq increasing to 20 brigades by May 2007 and remaining at that level through 

April 2009, the operational tempo of U.S. activecomponent ground combat forces increases—and the 

corresponding rotation ratio decreases—to a low of 0.9 

units at home station for every unit deployed (from 

February 2008 through August 2008). Thereafter, operational tempo declines and the rotation ratio increases 

toward (but does not reach during the time period CBO 

modeled) the stable level of 1.8 units at home station (see 

Figure 1). This case would require increasing the length 

of deployments to 15-month tours for active-component 

Army forces. The number of combat brigades immediately available to respond to other contingencies drops to 

a low of between 1.5 and 11.1 brigades in February 2009 

(assuming 12 or 6 months of recovery time) before rising 

toward between 7.6 and 16.7 at the end of calendar year

Jan.

2004

Jul.

2004

Jan.

2005

Jul.

2005

Jan.

2006

Jul.

2006

Jan.

2007

Jul.

2007

Jan.

2008

Jul.

2008

Jan.

2009

Jul.

2009

0

5

10

15

20

25

No Increase in Forces

4-Month Increase in Forces

12-Month Increase in Forces

24-Month Increase in Forces

Withdrawal of Forces

Goal

Forces for One Major Theater War
12 SOME IMPLICATIONS OF INCREASING U.S. FORCES IN IRAQ

2009 (see Figures 2 and 3).18 The Army National Guard’s 

combat brigades stabilize at about 7 units at home station 

for every unit deployed.

Scenario 5: Withdrawal of Forces

In this case, with U.S. forces in Iraq decreasing until 

complete withdrawal in July 2008, the operational tempo 

of U.S. active-component ground combat forces 

declines—and the corresponding rotation ratio increases 

rapidly—to a level of 14 units at home station for every 

unit deployed in August 2009. There is no need in this 

case to extend the length of deployment tours. The number of combat brigades immediately available to respond 

to other contingencies steadily increases to about 40 at 

the end of calendar year 2009. In this case, the Army 

National Guard’s combat brigades stabilize at about 24 

units at home station for every unit deployed. Once U.S. 

forces are withdrawn from Iraq, the only major deployments that must be sustained are those for Afghanistan 

and MEUs, implying that the bulk of U.S. ground forces 

are at their home station.

Rotation Ratios and Units Immediately 

Available: An Example

For all of CBO’s deployment scenarios other than withdrawal, U.S. forces in Iraq eventually decline to 15 combat brigades and remain there indefinitely. If that level of 

forces was maintained without change forever (as a hypothetical example), all other U.S. commitments remained 

stable, and the total number of Army and Marine Corps 

combat brigades remained stable, then the rotation ratio 

and number of combat brigades immediately available for 

other contingencies would approach a steady-state level. 

That level can be used to describe how CBO’s measures 

of the stress on the forces are generated and the effects 

that changes in force levels have on those measures.

At the steady-state level of 15 combat brigades in Iraq, 

the United States would have a supply of 52 activecomponent combat brigades (43 Army and 9 Marine 

Corps) and 31 reserve-component combat brigades (28 

Army National Guard and 3 Marine Corps Reserve). 

There would also be a steady U.S. commitment of 12 to 

13 active and two to three reserve combat brigades in Iraq 

(maintaining 15 at all times), two active combat brigades 

and one reserve combat brigade to Afghanistan, two 

active combat brigades to Korea and Okinawa, and one 

active combat brigade’s worth of forces dedicated to 

MEUs.

Assuming that all forces in Iraq and Afghanistan are 

deployed for 12-month tours and that they require a 

month each to deploy to the theater and redeploy to 

home station from the theater, there will be an additional 

three brigades that will be either deploying or redeploying 

at any one point, on average, over the course of a full 

year.19 Also, there will be one brigade recovering from a 

deployment for every brigade deployed, under the 

assumption that units have 12-month tours and require 

12 months to recover from a deployment.20 Under the 

assumption that units require 6 months to recover, there 

will be half as many units recovering from a deployment 

as are deployed. All active units (other than MEUs, which 

are deployed in order to be immediately available) that 

are not deployed, deploying, redeploying, or recovering 

from a deployment should be immediately available for 

other contingencies. In this case, with 52 active combat 

brigades, there would be 17.6 brigades immediately available (assuming 12 months for recovery after a deployment; see Table 3) to 25.3 brigades immediately available 

(assuming 6 months for recovery after a deployment; see 

Table 4).

For the rotation ratio, the supply of forces is 50 activecomponent brigades (the total of 52 minus the two allocated to Korea and Okinawa). The demand for forces is 

the number of forces deployed, deploying, or redeploying 

(17.9 for active-component forces, which comprises 15.5 

brigades deployed and 2.4 deploying or redeploying, and 

4.1 for reserve-component forces, which comprises 3.5

18. In this case, using 15-month tours for deployment causes a shortterm improvement in the number of combat brigades immediately available compared with the 4-month and 12-month 

increases around the January 2008 time frame. That improvement 

occurs because the transition to 15-month tours from 12-month 

tours essentially puts deployments to Iraq on pause for three 

months, allowing units at home station to recover. There is a similar, but much smaller, effect at work in the 12-month case (which 

uses fewer 15-month tours). 

19. Forces in Korea do not rotate to the theater but are instead stationed there permanently and, as such, do not require any 

time for deployment or redeployment. Similarly, MEUs, which 

are embarked on expeditionary strike groups, do not require additional time for deployment or redeployment.

20. Because they are stationed there permanently, forces in Korea do 

not require time to recover from deployment.
SOME IMPLICATIONS OF INCREASING U.S. FORCES IN IRAQ 13

Table 3.

Disposition of U.S. Combat Brigades for a Steady 15-Brigade Occupation of Iraq, 

Assuming 12 Months Is Required to Recover from a Deployment

Source: Congressional Budget Office.

Note: Numbers may not sum to totals because of rounding; n.a. = not applicable.

a. Because Marine expeditionary units (MEUs) are deployed in order to be rapidly available, the deployed MEUs are not tallied as unavailable.

deployed and 0.6 deploying or redeploying). The activecomponent rotation ratio is thus 50 divided by 17.9, 

minus 1—in other words, 1.8 units at home station for 

every unit deployed. The supply of reserve-component 

brigades is 31; hence, the reserve-component rotation 

ratio is 31 divided by 4.1, minus 1—or 6.6 units at home 

station for every unit deployed.

Because all of CBO’s modeled deployment scenarios 

other than the withdrawal case posit U.S. forces in Iraq 

eventually being reduced to 15 combat brigades (and 

then sustained at that level indefinitely), all of the scenarios converge toward those rotation ratios and numbers of 

brigades immediately available for deployment. In particular, rotation ratios converge toward the stable level of 

1.8 units at home station for every unit deployed relatively rapidly after the termination of the increase in U.S. 

forces in Iraq. Brigades available for immediate deployment, as a measure, lags somewhat more—assuming that 

12 months are required for units to recover from a 

deployment, the number of available brigades cannot 

begin to recover toward its stable level until 12 months 

after the termination of the increase in U.S. forces in 

Iraq.

Active Component

Iraq 12.5 2.1 12.5 27.1 n.a. n.a.

Afghanistan 2.0 0.3 2.0 4.3 n.a. n.a.

MEUs 1.0 n.a. 1.0 1.0a n.a. n.a. ____ ___ ____ ____

Subtotal, active 15.5 2.4 15.5 32.4 n.a. n.a.

Korea/Okinawa 2.0 n.a. n.a. 2.0 n.a. n.a. ____ ___ ____ ____

Total, active 17.5 2.4 15.5 34.4 17.6 52.0

Reserve Component

Iraq 2.5 0.4 n.a. n.a. n.a. n.a.

Afghanistan 1.0 0.2 n.a. n.a. n.a. n.a. ___ ___

Total, reserve 3.5 0.6 n.a. 4.1 26.9 31.0

Total

Deploying or 

Deployed Recovering Unavailable Available Redeploying
14 SOME IMPLICATIONS OF INCREASING U.S. FORCES IN IRAQ

Table 4.

Disposition of U.S. Combat Brigades for a Steady 15-Brigade Occupation of Iraq, 

Assuming 6 Months Is Required to Recover from a Deployment

Source: Congressional Budget Office.

Note: Numbers may not sum to totals because of rounding; n.a. = not applicable.

a. Because Marine expeditionary units (MEUs) are deployed in order to be rapidly available, the deployed MEUs are not tallied as unavailable.

Active Component

Iraq 12.5 2.1 6.3 20.8 n.a. n.a.

Afghanistan 2.0 0.3 1.0 3.3 n.a. n.a.

MEUs 1.0 n.a. 0.5 0.5a n.a. n.a. ____ ___ ___ ____

Subtotal, active 15.5 2.4 7.8 24.7 n.a. n.a.

Korea/Okinawa 2.0 n.a. n.a. 2.0 n.a. n.a. ____ ___ ___ ____

Total, active 17.5 2.4 7.8 26.7 25.3 52.0

Reserve Component

Iraq 2.5 0.4 n.a. n.a. n.a. n.a.

Afghanistan 1.0 0.2 n.a. n.a. n.a. n.a. ___ ___

Total, active 3.5 0.6 n.a. 4.1 26.9 31.0

Recovering Total

Deploying or 

Deployed Redeploying Unavailable Available