Resilience

Resilience asks a different question than the five core measures: not 'are you on track', but 'how well does your plan bend without breaking' - if income drops, or if inflation runs hot for years.

Flexibility

What it measures: discretionary spending as a share of your total budget - the portion you chose to spend, as opposed to the portion you have to spend.

The ideal band is 20% to 50%:

• Under 10% — "Rigid". Almost nothing left to cut if income drops.
• 10% to 20% — "Tight". Some room, but not much.
• 20% to 50% — "Balanced". The green band.
• 50% to 65% — "Very flexible".
• Above 65% — "Top-heavy".

Discretionary spending is what you could cut back in a pinch. Too little of it and a job loss or income gap has nowhere to absorb the hit except your essentials or your savings. Too much of it, on the other hand, usually means your "essential" baseline is drawn too narrowly to be a useful floor - keeping discretionary spending between a fifth and a half of the budget leaves genuine room to adapt without squeezing the expenses that can't wait.

Inflation protection

What it measures: the gap, in percentage points, between how much of your expenses rise with inflation and how much of your income does. A positive gap means your costs are outrunning your income's ability to keep up.

• Under 20 percentage points — "Protected". Green.
• 20 to 50 points — "Exposed". Amber.
• Above 50 points — "Highly exposed". Red.

Even a plan with healthy nominal cashflow can quietly lose ground if expenses climb with inflation faster than income does - rent and everyday costs tend to track inflation closely, while a fixed salary or a pension often doesn't. Keeping the gap under 20 points means your income is doing a reasonable job of keeping pace, so inflation isn't steadily eroding your plan's real purchasing power year after year.