Budget-Actual Variance Analysis
Overview
Analyzes the differences between budgeted and actual figures, identifying favorable and unfavorable variances with account-type awareness. Provides materiality ranking, root cause hypotheses, and actionable recommendations for management decision-making.
When to Use This Skill
Use this skill in the following scenarios:
- Monthly/Quarterly Budget Review - Compare actual results against budget to identify significant deviations
- 「今月の予実差異を分析して」「月次の予算対比レポートを作成して」
- Management Meeting Preparation - Create executive-level variance summaries with root cause analysis
- 「経営会議向けに予実サマリを作って」「取締役会用の業績報告資料を準備して」
- Cost Overrun Investigation - Identify which line items are over budget and why
- 「コスト超過の原因を特定して」「予算オーバーしている勘定科目を洗い出して」
- Revenue Shortfall Analysis - Determine revenue gaps and contributing factors
- 「売上未達の原因を分析して」「予算未達の要因分解をして」
- Rolling Forecast Adjustment - Use variance trends to update future projections
- 「差異トレンドから今後の見通しを修正して」「ローリングフォーキャストを更新して」
Prerequisites
Before running this skill, ensure the following data is available:
- Budget Data: Approved budget figures by account (CSV or manual input)
- Actual Data: Actual performance figures for the same period
- Account Classification: Each account must be classified as
revenue or cost/expense
- Period Information: Target analysis period (month, quarter, or year)
Required CSV Format
account_name,account_type,budget,actual
Sales Revenue,revenue,1000000,1200000
Material Cost,cost,400000,380000
Labor Cost,cost,300000,320000
Required Columns:
| Column |
Type |
Description |
account_name |
string |
Account or line item name |
account_type |
string |
revenue or cost (determines favorable/unfavorable logic) |
budget |
numeric |
Budgeted amount |
actual |
numeric |
Actual amount |
Workflow 1: Data Preparation
- Validate Input Format: Verify CSV structure and required columns are present
- Classify Accounts: Confirm account type assignments (revenue vs. cost/expense)
- Period Alignment: Ensure budget and actual figures correspond to the same period
- Data Cleansing: Handle missing values, zero budgets, and currency formatting
Workflow 2: Variance Calculation
- Compute Absolute Variance:
Variance = Actual - Budget for each line item
- Compute Percentage Variance:
Variance % = (Actual - Budget) / Budget * 100
- Determine Direction: Apply account-type-aware favorable/unfavorable logic:
| Account Type |
Actual > Budget |
Actual < Budget |
| Revenue |
Favorable (+) |
Unfavorable (-) |
| Cost/Expense |
Unfavorable (+) |
Favorable (-) |
- Materiality Ranking: Sort by absolute variance amount to highlight significant items
- Threshold Flagging: Flag items exceeding materiality threshold (default: 10% or top 5 items)
Workflow 3: Root Cause Analysis
- Pattern Identification: Look for correlated variances (e.g., higher sales + higher variable costs)
- Root Cause Hypotheses: For each material variance, suggest possible explanations:
- Revenue variances: volume changes, pricing changes, product mix shifts, seasonal effects
- Cost variances: input price changes, efficiency changes, activity level changes, one-time items
- Offsetting Analysis: Identify variances that partially cancel each other
- Trend Comparison: Compare current period variance to prior periods if data available
- Action Recommendations: Prioritized corrective actions for unfavorable variances
Output
The analysis produces a structured variance report containing:
- Executive Summary: Total favorable/unfavorable variance, key highlights
- Variance Detail Table: Per-account breakdown with amounts, percentages, and direction
- Materiality Ranking: Top variances sorted by absolute impact
- Root Cause Analysis: Hypotheses and supporting evidence for major variances
- Recommended Actions: Prioritized list of corrective/follow-up actions
Output template: assets/variance_report_template_ja.md (Japanese) or assets/variance_report_template_en.md (English)
Resources
References (load into context for guidance)
references/08_budget-actual-variance-analysis_20250820.md - Comprehensive guide on budget-actual variance analysis methodology with practical bakery business examples
references/05_evidence-based-budgeting_20250507.md - Budget planning fundamentals and evidence-based budgeting approaches
Assets (templates for output generation)
assets/variance_report_template_ja.md - Japanese variance analysis report template
assets/variance_report_template_en.md - English variance analysis report template
Best Practices
- Always verify account type classification before calculating variance direction
- Present both absolute amounts and percentages - large percentage on a small base may not be material
- Consider the business context: seasonal patterns, one-time events, and structural changes
- Look for offsetting variances - a favorable cost variance paired with unfavorable revenue may indicate reduced activity
- When budget assumptions have changed significantly, consider rebasing before analysis
- Focus management attention on actionable variances rather than uncontrollable factors
Examples
Example: Bakery Business Monthly Variance
Input Data:
account_name,account_type,budget,actual
Bread Sales,revenue,500000,480000
Cake Sales,revenue,300000,350000
Flour Cost,cost,120000,135000
Sugar Cost,cost,80000,75000
Labor Cost,cost,200000,210000
Rent,cost,100000,100000
Analysis Output (Summary):
- Total Revenue Variance: +30,000 (Favorable) - Cake sales overperformance offsets bread shortfall
- Total Cost Variance: +40,000 (Unfavorable) - Flour cost increase and overtime labor
- Net Variance: -10,000 (Unfavorable)
Key Findings:
- Cake Sales +50,000 (F): New seasonal menu drove demand
- Flour Cost +15,000 (U): Wheat price increase due to supply shortage
- Labor Cost +10,000 (U): Overtime to meet cake demand
- Bread Sales -20,000 (U): Competitor opened nearby - requires strategic response
1---2name: ma-budget-actual-variance3description: 予算実績差異分析スキル。勘定科目タイプ(収益/費用)に応じた有利・不利差異の自動判定、 差異の分解(価格差異・数量差異)、重要度ランキング、根本原因の仮説提示を行う。 CSVデータのアップロードによる自動分析に対応。 Use when: 予算と実績の比較分析を行いたいとき。月次・四半期の予実管理レポート作成、 差異の原因分析、経営会議向けの予実サマリ作成に使用。 Triggers: "予実差異", "予算実績", "budget variance", "budget vs actual", "予算対比", "差異分析", "variance analysis"4---56# Budget-Actual Variance Analysis78## Overview910Analyzes the differences between budgeted and actual figures, identifying favorable and unfavorable variances with account-type awareness. Provides materiality ranking, root cause hypotheses, and actionable recommendations for management decision-making.1112## When to Use This Skill1314Use this skill in the following scenarios:15161. **Monthly/Quarterly Budget Review** - Compare actual results against budget to identify significant deviations17 - 「今月の予実差異を分析して」「月次の予算対比レポートを作成して」182. **Management Meeting Preparation** - Create executive-level variance summaries with root cause analysis19 - 「経営会議向けに予実サマリを作って」「取締役会用の業績報告資料を準備して」203. **Cost Overrun Investigation** - Identify which line items are over budget and why21 - 「コスト超過の原因を特定して」「予算オーバーしている勘定科目を洗い出して」224. **Revenue Shortfall Analysis** - Determine revenue gaps and contributing factors23 - 「売上未達の原因を分析して」「予算未達の要因分解をして」245. **Rolling Forecast Adjustment** - Use variance trends to update future projections25 - 「差異トレンドから今後の見通しを修正して」「ローリングフォーキャストを更新して」2627## Prerequisites2829Before running this skill, ensure the following data is available:3031- **Budget Data**: Approved budget figures by account (CSV or manual input)32- **Actual Data**: Actual performance figures for the same period33- **Account Classification**: Each account must be classified as `revenue` or `cost`/`expense`34- **Period Information**: Target analysis period (month, quarter, or year)3536### Required CSV Format3738```csv39account_name,account_type,budget,actual40Sales Revenue,revenue,1000000,120000041Material Cost,cost,400000,38000042Labor Cost,cost,300000,32000043```4445**Required Columns:**46| Column | Type | Description |47|--------|------|-------------|48| `account_name` | string | Account or line item name |49| `account_type` | string | `revenue` or `cost` (determines favorable/unfavorable logic) |50| `budget` | numeric | Budgeted amount |51| `actual` | numeric | Actual amount |5253## Workflow 1: Data Preparation54551. **Validate Input Format**: Verify CSV structure and required columns are present562. **Classify Accounts**: Confirm account type assignments (revenue vs. cost/expense)573. **Period Alignment**: Ensure budget and actual figures correspond to the same period584. **Data Cleansing**: Handle missing values, zero budgets, and currency formatting5960## Workflow 2: Variance Calculation61621. **Compute Absolute Variance**: `Variance = Actual - Budget` for each line item632. **Compute Percentage Variance**: `Variance % = (Actual - Budget) / Budget * 100`643. **Determine Direction**: Apply account-type-aware favorable/unfavorable logic:6566| Account Type | Actual > Budget | Actual < Budget |67|-------------|----------------|----------------|68| Revenue | Favorable (+) | Unfavorable (-) |69| Cost/Expense | Unfavorable (+) | Favorable (-) |70714. **Materiality Ranking**: Sort by absolute variance amount to highlight significant items725. **Threshold Flagging**: Flag items exceeding materiality threshold (default: 10% or top 5 items)7374## Workflow 3: Root Cause Analysis75761. **Pattern Identification**: Look for correlated variances (e.g., higher sales + higher variable costs)772. **Root Cause Hypotheses**: For each material variance, suggest possible explanations:78 - Revenue variances: volume changes, pricing changes, product mix shifts, seasonal effects79 - Cost variances: input price changes, efficiency changes, activity level changes, one-time items803. **Offsetting Analysis**: Identify variances that partially cancel each other814. **Trend Comparison**: Compare current period variance to prior periods if data available825. **Action Recommendations**: Prioritized corrective actions for unfavorable variances8384## Output8586The analysis produces a structured variance report containing:87881. **Executive Summary**: Total favorable/unfavorable variance, key highlights892. **Variance Detail Table**: Per-account breakdown with amounts, percentages, and direction903. **Materiality Ranking**: Top variances sorted by absolute impact914. **Root Cause Analysis**: Hypotheses and supporting evidence for major variances925. **Recommended Actions**: Prioritized list of corrective/follow-up actions9394Output template: `assets/variance_report_template_ja.md` (Japanese) or `assets/variance_report_template_en.md` (English)9596## Resources9798### References (load into context for guidance)99100- `references/08_budget-actual-variance-analysis_20250820.md` - Comprehensive guide on budget-actual variance analysis methodology with practical bakery business examples101- `references/05_evidence-based-budgeting_20250507.md` - Budget planning fundamentals and evidence-based budgeting approaches102103### Assets (templates for output generation)104105- `assets/variance_report_template_ja.md` - Japanese variance analysis report template106- `assets/variance_report_template_en.md` - English variance analysis report template107108## Best Practices109110- Always verify account type classification before calculating variance direction111- Present both absolute amounts and percentages - large percentage on a small base may not be material112- Consider the business context: seasonal patterns, one-time events, and structural changes113- Look for offsetting variances - a favorable cost variance paired with unfavorable revenue may indicate reduced activity114- When budget assumptions have changed significantly, consider rebasing before analysis115- Focus management attention on actionable variances rather than uncontrollable factors116117## Examples118119### Example: Bakery Business Monthly Variance120121**Input Data:**122```csv123account_name,account_type,budget,actual124Bread Sales,revenue,500000,480000125Cake Sales,revenue,300000,350000126Flour Cost,cost,120000,135000127Sugar Cost,cost,80000,75000128Labor Cost,cost,200000,210000129Rent,cost,100000,100000130```131132**Analysis Output (Summary):**133- Total Revenue Variance: +30,000 (Favorable) - Cake sales overperformance offsets bread shortfall134- Total Cost Variance: +40,000 (Unfavorable) - Flour cost increase and overtime labor135- Net Variance: -10,000 (Unfavorable)136137**Key Findings:**1381. Cake Sales +50,000 (F): New seasonal menu drove demand1392. Flour Cost +15,000 (U): Wheat price increase due to supply shortage1403. Labor Cost +10,000 (U): Overtime to meet cake demand1414. Bread Sales -20,000 (U): Competitor opened nearby - requires strategic response