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---
technique: performing-security-roi-analysis
subdomain: security-leadership
title: "Performing Security ROI Analysis"
description: "Techniques and methodologies for performing security roi analysis"
tags:
  - ROI
  - cost-analysis
  - risk-quantification
  - FAIR
  - business-case
metadata:
  mitre-attack: []
---

# Performing Security ROI Analysis

> Quantify the return on investment for security initiatives by modeling cost avoidance, risk reduction, and operational efficiency gains.

## Overview

Security ROI analysis provides the financial justification for security investments by quantifying expected losses avoided, operational savings, and compliance cost reduction. This technique uses FAIR-based risk quantification and cost-benefit modeling.

## Core Concepts

- **Annualized Loss Expectancy (ALE)**: Frequency × magnitude of expected losses
- **FAIR model**: Factor Analysis of Information Risk for quantitative risk assessment
- **Cost avoidance**: Reduction in expected breach costs, fines, and remediation
- **Operational efficiency**: Time saved through automation and tooling improvements
- **Payback period**: Time for security investment to offset its cost through risk reduction

## Workflow

1. Define the security initiative and its intended risk reduction
2. Model current risk exposure using FAIR methodology
3. Estimate post-initiative risk exposure
4. Calculate ALE reduction (risk delta)
5. Itemize initiative costs: capital, operational, and opportunity
6. Compute ROI as (ALE reduction - costs) / costs
7. Calculate payback period and break-even point
8. Perform sensitivity analysis on key assumptions
9. Build executive presentation with scenario comparisons
10. Track actual outcomes post-implementation for model calibration

## Implementation

```python
from dataclasses import dataclass
from typing import Optional


@dataclass
class RiskScenario:
    name: str
    frequency_per_year: float
    loss_magnitude_low: float
    loss_magnitude_high: float
    loss_magnitude_likely: float

    @property
    def ale(self) -> float:
        expected_loss = (self.loss_magnitude_low + 4 * self.loss_magnitude_likely + self.loss_magnitude_high) / 6
        return round(self.frequency_per_year * expected_loss, 2)


@dataclass
class SecurityInvestment:
    name: str
    capital_cost: float
    annual_operating_cost: float
    implementation_months: int

    @property
    def first_year_cost(self) -> float:
        return self.capital_cost + self.annual_operating_cost


class ROIAnalyzer:
    """Security investment ROI analysis using FAIR methodology."""

    def __init__(self) -> None:
        self.current_risk: RiskScenario | None = None
        self.residual_risk: RiskScenario | None = None
        self.investment: SecurityInvestment | None = None

    def set_scenario(self, current: RiskScenario, residual: RiskScenario, investment: SecurityInvestment) -> None:
        self.current_risk = current
        self.residual_risk = residual
        self.investment = investment

    def ale_reduction(self) -> float:
        if not self.current_risk or not self.residual_risk:
            return 0.0
        return round(self.current_risk.ale - self.residual_risk.ale, 2)

    def roi_percentage(self) -> float:
        if not self.investment:
            return 0.0
        cost = self.investment.first_year_cost
        return round((self.ale_reduction() - cost) / cost * 100, 2) if cost > 0 else 0.0

    def payback_months(self) -> float:
        if not self.investment:
            return 0.0
        monthly_benefit = self.ale_reduction() / 12
        if monthly_benefit <= 0:
            return float("inf")
        return round(self.investment.first_year_cost / monthly_benefit, 1)

    def summary(self) -> dict:
        return {
            "ale_reduction": self.ale_reduction(),
            "roi_percentage": self.roi_percentage(),
            "payback_months": self.payback_months(),
            "first_year_cost": self.investment.first_year_cost if self.investment else 0,
        }
```

## Best Practices

- Use ranges, not point estimates—security risk is inherently uncertain
- Present ROI as risk reduction, not profit—security is cost avoidance
- Include indirect costs: reputation damage, customer churn, regulatory fines
- Calibrate models against actual incident costs when available
- Run sensitivity analysis on frequency and magnitude assumptions
- Update ROI models annually with actual loss data for improved accuracy

## Related Techniques

- [Implementing Security Roadmap Planning](../implementing-security-roadmap-planning/SKILL.md)
- [Building Security Executive Dashboard](../building-security-executive-dashboard/SKILL.md)
