P50 Median TCO
Most likely outcome
P90 (Worst 10%)
+$530k vs baseline
P10 (Best 10%)
−$400k vs baseline
Risk Range P10→P90
σ = $285k · n=1000
Risk Contribution to TCO Variance
Failure-rate uncertainty is now the largest driver (22%). Condition-based maintenance and reman parts tighten this distribution the most.
Percentile Outcomes
| Percentile | TCO | vs Baseline |
|---|---|---|
| P5 (Best) | $3.28M | −$540k (−14%) |
| P10 | $3.42M | −$400k (−10%) |
| P25 | $3.61M | −$210k (−5%) |
| P50 (Median) | $3.82M | — |
| P75 | $4.08M | +$260k (+7%) |
| P90 | $4.35M | +$530k (+14%) |
| P95 (Worst) | $4.58M | +$760k (+20%) |
Randomized Input Distributions
| Input | Distribution | Min | Max | Std Dev |
|---|---|---|---|---|
| Fuel Price | Log-normal | $1.10 | $2.80 | $0.35 |
| Failure Rate | Gamma | 0.5× | 3.0× | 0.4× |
| Labor Rate | Normal | $75 | $145 | $18 |
| Inflation (Labor) | Normal | 1.5% | 6.5% | 1.0% |
Each run samples all four inputs and re-computes the full 20-year TCO with Weibull failure draws.