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GARP Chapter 18: Why 20 Plus 20 Is Not 40

The Combined Values Chart, in plain English. Why your points never add up, and what that means for where you put your effort.

This is the chapter that explains why your points do not add up the way you expect.

20 plus 20 is 36

Once every condition has a number, they have to become one number. They are not added. They are joined using a chart.

The idea is called whole person impairment. You are one whole person. If a condition takes 20% of you, there is 80% of you left. The next condition can only take a share of that 80%.

So 20 and 20 gives 36, not 40. The chart does 20 + (20% of the remaining 80) = 20 + 16 = 36.

The Guide's own example

Three conditions, worth 60, 30 and 10.

  • First condition: 60. You are 60% impaired. 40 left.
  • Second condition: 30% of the remaining 40 = 12. Total 72.
  • Third condition: 10% of the remaining 28 = 3 (rounded). Total 75.

Straight addition would have said 100. The chart says 75.

Order does not matter

The chart is applied highest first, then the next highest, and so on. But you end up at the same place regardless. There is no way to game the order.

What this actually means for your claim

Three practical consequences.

1. Small conditions matter most when your total is low. If you are on 10 points, a 5-point condition adds about 4 or 5. If you are on 70 points, the same condition adds about 1 or 2.

2. There is no way to reach 100. Each new condition takes a slice of a shrinking remainder. Very high totals require very severe individual ratings, not lots of small ones.

3. It makes one thing far more valuable than the rest: getting your biggest condition rated correctly. Ten extra points on your worst condition is worth much more than three new small conditions.

So if you are choosing where to put your effort, put it into the accurate assessment of your worst problem.

Where this chart is not used

Two important exceptions.

  • Chapter 4, mental health. Those five numbers are added straight up. The chart is not used.
  • Chapter 3, resting joint pain. That one is an additional rating on top.

What this means for you

  • Do not expect your points to add up. They will always be less than the sum.
  • Focus on your worst condition first. That is where the leverage is.
  • Still claim the small ones — especially if your total is low, where they are worth most.
  • Do not let anyone tell you it is a mistake. It is the chart working as designed.

Common questions

Is this DVA cutting my payment?

No. It is a fixed chart in the legislated Guide, applied the same way to everyone.

Can the order change my total?

No. The result is the same however the ratings are ordered.

Why is my mate on 70 getting nothing extra for a new condition?

Because at 70 there is only 30 of the whole person left, and a new condition takes a share of that 30. High totals are hard to move.

Next in this series

Chapter 19: when something not accepted is part of the problem.

Want a hand with yours?

If you have a permanent impairment assessment coming up, we do these every week. Call 0429 146 039 or email reception@vhc.org.au.

More reading

What is the GARP? · The chapter map · DVA Claims: PI points calculator · Permanent Impairment Assessments · DVA claims · SoP library

This is general information for Australian veterans. It is not legal advice. It explains Chapter 18 of the Guide to Determining Impairment and Compensation 2026 (F2026L00595), which started on 1 July 2026. The full rules are on the Federal Register of Legislation. Check your own situation with DVA on 1800 VETERAN (1800 838 372).

Your doctor

Dr Thomas Perkins

The expert in veterans’ medicolegal medicine — Expert DVA Doctor.

Dr Thomas Perkins is the founding doctor at the Veterans Health Centre in Ipswich, Queensland, and the leading expert in veterans’ medicolegal work in Australia. He has spent over 13 years working exclusively with current and former Australian Defence Force members — treating conditions, writing reports, and navigating the DVA system alongside them.

With 100,000+ DVA claims submitted and over 2,000 Permanent Impairment Assessments completed, Dr Perkins brings a depth of experience that simply cannot be replicated from a textbook. He understands the Statements of Principles, the GARP tables, the imaging that proves what a physical examination alone cannot — and the difference that a properly written report makes at every level, from initial liability through to the VRB.

Every chart review, every diagnostic assessment, and every impairment rating is personally overseen by Dr Perkins. If you’re looking for a doctor who knows veterans medicine inside and out, you’ve found the right clinic.

Contact us0429 146 039 reception@vhc.org.au

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