More Combat Results Tables from War by Numbers

Now, the purpose of War by Numbers was not to create Combat Results Tables (CRT) for wargames. Its real purpose was to test the theoretical ideas of Clausewitz, and more particularly, Trevor N. Dupuy to actual real-world data. Not as case studies, but as statistical compilations that would show what the norms are. Unfortunately, military history is often the study of exceptions, or exceptional events, and what is often lost to the casual reader it what the norms are. Properly developed statistical database will clearly show what the norms are and how frequent or infrequent these exceptions are. People tend to remember the exceptional cases, they tend to forget the norms, if they even knew what they were to start with.

Chapters 3, 4 and 5 of War by Numbers is primarily focused on measuring human factors (which some people in the U.S. DOD analytical community seem to think are unmeasurable, even though we are measuring them). As part of that effort I ended up assemble a set of force ratios tables based upon theater and nationality. The first of these, on page 10, was in my previous blog post. Here are a few others, from page 11 of War by Numbers.

Germans attacking Soviets (Battles of Kharkov and Kursk), 1943


Force Ratio                          Result                                    Percent Failure   Number of cases

0.63 to 1.06-to-1.00             Attack usually succeeds      20%                        5

1.18 to 1.87-to-1.00             Attack usually succeeds        6%                      17

1.91-to-1.00 and higher      Attacker Advances                 0%                       21


Soviets attacking Germans (Battles of Kharkov and Kursk), 1943


Force Ratio                          Result                                    Percent Failure   Number of cases

0.40 to 1.05-to-1                  Attack usually fails                70%                      10

1.20 to 1.65-to-1.00             Attack often fails                    50%                      11

1.91 to 2.89-to-1.00             Attack sometimes fails          44%                       9




Pacific Theater of Operations (PTO) Data, U.S. attacking Japanese, 1945


Force Ratio                          Result                                    Percent Failure   Number of cases

1.40 to 2.89-to-1.00             Attack succeeds                        0%                     20

2.92 to 3.89-to-1.00             Attack usually succeeds        21%                      14

4.35-to-1.00 and higher       Attack usually succeeds          4%                     26


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Christopher A. Lawrence
Christopher A. Lawrence

Christopher A. Lawrence is a professional historian and military analyst. He is the Executive Director and President of The Dupuy Institute, an organization dedicated to scholarly research and objective analysis of historical data related to armed conflict and the resolution of armed conflict. The Dupuy Institute provides independent, historically-based analyses of lessons learned from modern military experience.
Mr. Lawrence was the program manager for the Ardennes Campaign Simulation Data Base, the Kursk Data Base, the Modern Insurgency Spread Sheets and for a number of other smaller combat data bases. He has participated in casualty estimation studies (including estimates for Bosnia and Iraq) and studies of air campaign modeling, enemy prisoner of war capture rates, medium weight armor, urban warfare, situational awareness, counterinsurgency and other subjects for the U.S. Army, the Defense Department, the Joint Staff and the U.S. Air Force. He has also directed a number of studies related to the military impact of banning antipersonnel mines for the Joint Staff, Los Alamos National Laboratories and the Vietnam Veterans of American Foundation.
His published works include papers and monographs for the Congressional Office of Technology Assessment and the Vietnam Veterans of American Foundation, in addition to over 40 articles written for limited-distribution newsletters and over 60 analytical reports prepared for the Defense Department. He is the author of Kursk: The Battle of Prokhorovka (Aberdeen Books, Sheridan, CO., 2015), America’s Modern Wars: Understanding Iraq, Afghanistan and Vietnam (Casemate Publishers, Philadelphia & Oxford, 2015), War by Numbers: Understanding Conventional Combat (Potomac Books, Lincoln, NE., 2017) , The Battle of Prokhorovka (Stackpole Books, Guilford, CT., 2019), The Battle for Kyiv (Frontline Books, Yorkshire, UK, 2023), Aces at Kursk (Air World, Yorkshire, UK, 2024), Hunting Falcon: The Story of WWI German Ace Hans-Joachim Buddecke (Air World, Yorkshire, UK, 2024) and The Siege of Mariupol (Frontline Books, Yorkshire, UK, 2024).
Mr. Lawrence lives in northern Virginia, near Washington, D.C., with his wife and son.

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  1. Have total strength to force ratios been compared before, i.e. at what strength the attack usually succeeded in contrast to the respective ratio (and level)?
    Another issue of course is to know whether these cases constitute typical engagements, but then again there may be no such thing as an outlier in combat, just missing context.

    • Not sure I understand the question. The process is described in Chapter 2 (Force Ratios) of War by Numbers and the actual data used in the construction of these tables is shown in the reference TDI (The Dupuy Institute) reports.

  2. In the battles/engagements you reference above, are they all at the same “echelon” or are they a mix of sizes. Or do you believe that determining the combat power ratio normalizes the engagement so you can compare a battalion sized attack against a company with a regimental or division sized attack against a battalion?

    And back to “usually” perhaps it would be better if the chart said:

    Force Ratio %Attacker Success % Defender Success Cases
    0.40 to 1.05-to-1 70 30 10
    1.20 to 1.65-to-1.00 51 49 11
    1.91 to 2.89-to-1.00 66 44 9

  3. Chris, the soviet and german force ratios are differing. Is this b/c of a lack of data? It also seems to have an influence on the failure percentage of the soviet forces.

    Furthermore, the available PTO data suggest that force ratios are not very useful to interpret battle results. If a much better force ratio leads to a much higher chance of failure, something seems off. I assume this is also due to a lack of data?

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