🎁 Get the FREE AI Skills Starter Guide β€” Subscribe β†’
BytesAgainBytesAgain
πŸ¦€ ClawHub

Cwicr Cost Calculator

by @datadrivenconstruction

Calculate construction costs using DDC CWICR resource-based methodology. Break down costs into labor, materials, equipment with transparent pricing.

Versionv2.1.0
Downloads1,548
Installs1
TERMINAL
clawhub install cwicr-cost-calculator

πŸ“– About This Skill


name: "cwicr-cost-calculator" description: "Calculate construction costs using DDC CWICR resource-based methodology. Break down costs into labor, materials, equipment with transparent pricing." homepage: "https://datadrivenconstruction.io" metadata: {"openclaw":{"emoji":"πŸ’°","os":["darwin","linux","win32"],"homepage":"https://datadrivenconstruction.io","requires":{"bins":["python3"]}}}

CWICR Cost Calculator

Business Case

Problem Statement

Traditional cost estimation often produces "black box" estimates with hidden markups. Stakeholders need:
  • Transparent cost breakdowns
  • Traceable pricing logic
  • Auditable calculations
  • Resource-level detail
  • Solution

    Resource-based cost calculation using CWICR methodology that separates physical norms (labor hours, material quantities) from volatile prices, enabling transparent and auditable estimates.

    Business Value

  • Full transparency - Every cost component visible
  • Auditable - Traceable calculation logic
  • Flexible - Update prices without changing norms
  • Accurate - Based on 55,000+ validated work items
  • Technical Implementation

    Prerequisites

    pip install pandas numpy
    

    Python Implementation

    import pandas as pd
    import numpy as np
    from typing import Dict, Any, List, Optional, Tuple
    from dataclasses import dataclass, field
    from enum import Enum
    from datetime import datetime

    class CostComponent(Enum): """Cost breakdown components.""" LABOR = "labor" MATERIAL = "material" EQUIPMENT = "equipment" OVERHEAD = "overhead" PROFIT = "profit" TOTAL = "total"

    class CostStatus(Enum): """Cost calculation status.""" CALCULATED = "calculated" ESTIMATED = "estimated" MISSING_DATA = "missing_data" ERROR = "error"

    @dataclass class CostBreakdown: """Detailed cost breakdown for a work item.""" work_item_code: str description: str unit: str quantity: float

    labor_cost: float = 0.0 material_cost: float = 0.0 equipment_cost: float = 0.0 overhead_cost: float = 0.0 profit_cost: float = 0.0

    unit_price: float = 0.0 total_cost: float = 0.0

    labor_hours: float = 0.0 labor_rate: float = 0.0

    resources: List[Dict[str, Any]] = field(default_factory=list) status: CostStatus = CostStatus.CALCULATED

    def to_dict(self) -> Dict[str, Any]: return { 'work_item_code': self.work_item_code, 'description': self.description, 'unit': self.unit, 'quantity': self.quantity, 'labor_cost': self.labor_cost, 'material_cost': self.material_cost, 'equipment_cost': self.equipment_cost, 'overhead_cost': self.overhead_cost, 'profit_cost': self.profit_cost, 'total_cost': self.total_cost, 'status': self.status.value }

    @dataclass class CostSummary: """Summary of cost estimate.""" total_cost: float labor_total: float material_total: float equipment_total: float overhead_total: float profit_total: float

    item_count: int currency: str calculated_at: datetime

    breakdown_by_category: Dict[str, float] = field(default_factory=dict)

    class CWICRCostCalculator: """Resource-based cost calculator using CWICR methodology."""

    DEFAULT_OVERHEAD_RATE = 0.15 # 15% overhead DEFAULT_PROFIT_RATE = 0.10 # 10% profit

    def __init__(self, cwicr_data: pd.DataFrame, overhead_rate: float = None, profit_rate: float = None, currency: str = "USD"): """Initialize calculator with CWICR data.""" self.data = cwicr_data self.overhead_rate = overhead_rate or self.DEFAULT_OVERHEAD_RATE self.profit_rate = profit_rate or self.DEFAULT_PROFIT_RATE self.currency = currency

    # Index data for fast lookup self._index_data()

    def _index_data(self): """Create index for fast work item lookup.""" if 'work_item_code' in self.data.columns: self._code_index = self.data.set_index('work_item_code') else: self._code_index = None

    def calculate_item_cost(self, work_item_code: str, quantity: float, price_overrides: Dict[str, float] = None) -> CostBreakdown: """Calculate cost for single work item."""

    # Find work item in database if self._code_index is not None and work_item_code in self._code_index.index: item = self._code_index.loc[work_item_code] else: # Try partial match matches = self.data[ self.data['work_item_code'].str.contains(work_item_code, case=False, na=False) ] if matches.empty: return CostBreakdown( work_item_code=work_item_code, description="NOT FOUND", unit="", quantity=quantity, status=CostStatus.MISSING_DATA ) item = matches.iloc[0]

    # Get base costs labor_unit = float(item.get('labor_cost', 0) or 0) material_unit = float(item.get('material_cost', 0) or 0) equipment_unit = float(item.get('equipment_cost', 0) or 0)

    # Apply price overrides if provided if price_overrides: if 'labor_rate' in price_overrides: labor_norm = float(item.get('labor_norm', 0) or 0) labor_unit = labor_norm * price_overrides['labor_rate'] if 'material_factor' in price_overrides: material_unit *= price_overrides['material_factor'] if 'equipment_factor' in price_overrides: equipment_unit *= price_overrides['equipment_factor']

    # Calculate component costs labor_cost = labor_unit * quantity material_cost = material_unit * quantity equipment_cost = equipment_unit * quantity

    # Direct costs direct_cost = labor_cost + material_cost + equipment_cost

    # Overhead and profit overhead_cost = direct_cost * self.overhead_rate profit_cost = (direct_cost + overhead_cost) * self.profit_rate

    # Total total_cost = direct_cost + overhead_cost + profit_cost

    # Unit price unit_price = total_cost / quantity if quantity > 0 else 0

    return CostBreakdown( work_item_code=work_item_code, description=str(item.get('description', '')), unit=str(item.get('unit', '')), quantity=quantity, labor_cost=labor_cost, material_cost=material_cost, equipment_cost=equipment_cost, overhead_cost=overhead_cost, profit_cost=profit_cost, unit_price=unit_price, total_cost=total_cost, labor_hours=float(item.get('labor_norm', 0) or 0) * quantity, labor_rate=float(item.get('labor_rate', 0) or 0), status=CostStatus.CALCULATED )

    def calculate_estimate(self, items: List[Dict[str, Any]], group_by_category: bool = True) -> CostSummary: """Calculate cost estimate for multiple items."""

    breakdowns = [] for item in items: code = item.get('work_item_code') or item.get('code') qty = item.get('quantity', 0) overrides = item.get('price_overrides')

    breakdown = self.calculate_item_cost(code, qty, overrides) breakdowns.append(breakdown)

    # Aggregate totals labor_total = sum(b.labor_cost for b in breakdowns) material_total = sum(b.material_cost for b in breakdowns) equipment_total = sum(b.equipment_cost for b in breakdowns) overhead_total = sum(b.overhead_cost for b in breakdowns) profit_total = sum(b.profit_cost for b in breakdowns) total_cost = sum(b.total_cost for b in breakdowns)

    # Group by category if requested breakdown_by_category = {} if group_by_category: for b in breakdowns: # Extract category from work item code prefix category = b.work_item_code.split('-')[0] if '-' in b.work_item_code else 'Other' if category not in breakdown_by_category: breakdown_by_category[category] = 0 breakdown_by_category[category] += b.total_cost

    return CostSummary( total_cost=total_cost, labor_total=labor_total, material_total=material_total, equipment_total=equipment_total, overhead_total=overhead_total, profit_total=profit_total, item_count=len(breakdowns), currency=self.currency, calculated_at=datetime.now(), breakdown_by_category=breakdown_by_category )

    def calculate_from_qto(self, qto_df: pd.DataFrame, code_column: str = 'work_item_code', quantity_column: str = 'quantity') -> pd.DataFrame: """Calculate costs from Quantity Takeoff DataFrame."""

    results = [] for _, row in qto_df.iterrows(): code = row[code_column] qty = row[quantity_column]

    breakdown = self.calculate_item_cost(code, qty) result = breakdown.to_dict()

    # Add original QTO columns for col in qto_df.columns: if col not in result: result[f'qto_{col}'] = row[col]

    results.append(result)

    return pd.DataFrame(results)

    def apply_regional_factors(self, base_costs: pd.DataFrame, region_factors: Dict[str, float]) -> pd.DataFrame: """Apply regional adjustment factors.""" adjusted = base_costs.copy()

    if 'labor_cost' in adjusted.columns and 'labor' in region_factors: adjusted['labor_cost'] *= region_factors['labor']

    if 'material_cost' in adjusted.columns and 'material' in region_factors: adjusted['material_cost'] *= region_factors['material']

    if 'equipment_cost' in adjusted.columns and 'equipment' in region_factors: adjusted['equipment_cost'] *= region_factors['equipment']

    # Recalculate totals adjusted['direct_cost'] = ( adjusted.get('labor_cost', 0) + adjusted.get('material_cost', 0) + adjusted.get('equipment_cost', 0) ) adjusted['total_cost'] = adjusted['direct_cost'] * (1 + self.overhead_rate) * (1 + self.profit_rate)

    return adjusted

    def compare_estimates(self, estimate1: CostSummary, estimate2: CostSummary) -> Dict[str, Any]: """Compare two cost estimates.""" return { 'total_difference': estimate2.total_cost - estimate1.total_cost, 'total_percent_change': ( (estimate2.total_cost - estimate1.total_cost) / estimate1.total_cost * 100 if estimate1.total_cost > 0 else 0 ), 'labor_difference': estimate2.labor_total - estimate1.labor_total, 'material_difference': estimate2.material_total - estimate1.material_total, 'equipment_difference': estimate2.equipment_total - estimate1.equipment_total, 'item_count_difference': estimate2.item_count - estimate1.item_count }

    class CostReportGenerator: """Generate cost reports from calculations."""

    def __init__(self, calculator: CWICRCostCalculator): self.calculator = calculator

    def generate_summary_report(self, items: List[Dict[str, Any]]) -> Dict[str, Any]: """Generate summary cost report.""" summary = self.calculator.calculate_estimate(items)

    return { 'report_date': datetime.now().isoformat(), 'currency': summary.currency, 'total_cost': round(summary.total_cost, 2), 'breakdown': { 'labor': round(summary.labor_total, 2), 'material': round(summary.material_total, 2), 'equipment': round(summary.equipment_total, 2), 'overhead': round(summary.overhead_total, 2), 'profit': round(summary.profit_total, 2) }, 'percentages': { 'labor': round(summary.labor_total / summary.total_cost * 100, 1) if summary.total_cost > 0 else 0, 'material': round(summary.material_total / summary.total_cost * 100, 1) if summary.total_cost > 0 else 0, 'equipment': round(summary.equipment_total / summary.total_cost * 100, 1) if summary.total_cost > 0 else 0, }, 'item_count': summary.item_count, 'by_category': summary.breakdown_by_category }

    def generate_detailed_report(self, items: List[Dict[str, Any]]) -> pd.DataFrame: """Generate detailed line-item report.""" results = []

    for item in items: code = item.get('work_item_code') or item.get('code') qty = item.get('quantity', 0)

    breakdown = self.calculator.calculate_item_cost(code, qty) results.append(breakdown.to_dict())

    df = pd.DataFrame(results)

    # Add totals row totals = df[['labor_cost', 'material_cost', 'equipment_cost', 'overhead_cost', 'profit_cost', 'total_cost']].sum() totals['description'] = 'TOTAL' totals['work_item_code'] = ''

    df = pd.concat([df, pd.DataFrame([totals])], ignore_index=True)

    return df

    Convenience functions

    def calculate_cost(cwicr_data: pd.DataFrame, work_item_code: str, quantity: float) -> float: """Quick cost calculation.""" calc = CWICRCostCalculator(cwicr_data) breakdown = calc.calculate_item_cost(work_item_code, quantity) return breakdown.total_cost

    def estimate_project_cost(cwicr_data: pd.DataFrame, items: List[Dict[str, Any]]) -> Dict[str, Any]: """Quick project cost estimate.""" calc = CWICRCostCalculator(cwicr_data) report = CostReportGenerator(calc) return report.generate_summary_report(items)

    Quick Start

    import pandas as pd
    from cwicr_data_loader import CWICRDataLoader

    Load CWICR data

    loader = CWICRDataLoader() cwicr = loader.load("ddc_cwicr_en.parquet")

    Initialize calculator

    calc = CWICRCostCalculator(cwicr)

    Calculate single item

    breakdown = calc.calculate_item_cost("CONC-001", quantity=150) print(f"Total: ${breakdown.total_cost:,.2f}") print(f" Labor: ${breakdown.labor_cost:,.2f}") print(f" Material: ${breakdown.material_cost:,.2f}") print(f" Equipment: ${breakdown.equipment_cost:,.2f}")

    Common Use Cases

    1. Project Estimate

    items = [
        {'work_item_code': 'CONC-001', 'quantity': 150},
        {'work_item_code': 'EXCV-002', 'quantity': 200},
        {'work_item_code': 'REBAR-003', 'quantity': 15000}  # kg
    ]

    summary = calc.calculate_estimate(items) print(f"Project Total: ${summary.total_cost:,.2f}")

    2. QTO Integration

    # Load BIM quantities
    qto = pd.read_excel("quantities.xlsx")

    Calculate costs

    costs = calc.calculate_from_qto(qto, code_column='work_item', quantity_column='quantity' ) print(costs[['description', 'quantity', 'total_cost']])

    3. Regional Adjustment

    # Apply Berlin pricing
    berlin_factors = {
        'labor': 1.15,      # 15% higher labor
        'material': 0.95,   # 5% lower materials
        'equipment': 1.0
    }

    adjusted = calc.apply_regional_factors(costs, berlin_factors)

    Resources

  • GitHub: OpenConstructionEstimate-DDC-CWICR
  • DDC Book: Chapter 3.1 - Construction Cost Estimation
  • πŸ’‘ Examples

    import pandas as pd
    from cwicr_data_loader import CWICRDataLoader

    Load CWICR data

    loader = CWICRDataLoader() cwicr = loader.load("ddc_cwicr_en.parquet")

    Initialize calculator

    calc = CWICRCostCalculator(cwicr)

    Calculate single item

    breakdown = calc.calculate_item_cost("CONC-001", quantity=150) print(f"Total: ${breakdown.total_cost:,.2f}") print(f" Labor: ${breakdown.labor_cost:,.2f}") print(f" Material: ${breakdown.material_cost:,.2f}") print(f" Equipment: ${breakdown.equipment_cost:,.2f}")

    βš™οΈ Configuration

    pip install pandas numpy
    

    Python Implementation

    import pandas as pd
    import numpy as np
    from typing import Dict, Any, List, Optional, Tuple
    from dataclasses import dataclass, field
    from enum import Enum
    from datetime import datetime

    class CostComponent(Enum): """Cost breakdown components.""" LABOR = "labor" MATERIAL = "material" EQUIPMENT = "equipment" OVERHEAD = "overhead" PROFIT = "profit" TOTAL = "total"

    class CostStatus(Enum): """Cost calculation status.""" CALCULATED = "calculated" ESTIMATED = "estimated" MISSING_DATA = "missing_data" ERROR = "error"

    @dataclass class CostBreakdown: """Detailed cost breakdown for a work item.""" work_item_code: str description: str unit: str quantity: float

    labor_cost: float = 0.0 material_cost: float = 0.0 equipment_cost: float = 0.0 overhead_cost: float = 0.0 profit_cost: float = 0.0

    unit_price: float = 0.0 total_cost: float = 0.0

    labor_hours: float = 0.0 labor_rate: float = 0.0

    resources: List[Dict[str, Any]] = field(default_factory=list) status: CostStatus = CostStatus.CALCULATED

    def to_dict(self) -> Dict[str, Any]: return { 'work_item_code': self.work_item_code, 'description': self.description, 'unit': self.unit, 'quantity': self.quantity, 'labor_cost': self.labor_cost, 'material_cost': self.material_cost, 'equipment_cost': self.equipment_cost, 'overhead_cost': self.overhead_cost, 'profit_cost': self.profit_cost, 'total_cost': self.total_cost, 'status': self.status.value }

    @dataclass class CostSummary: """Summary of cost estimate.""" total_cost: float labor_total: float material_total: float equipment_total: float overhead_total: float profit_total: float

    item_count: int currency: str calculated_at: datetime

    breakdown_by_category: Dict[str, float] = field(default_factory=dict)

    class CWICRCostCalculator: """Resource-based cost calculator using CWICR methodology."""

    DEFAULT_OVERHEAD_RATE = 0.15 # 15% overhead DEFAULT_PROFIT_RATE = 0.10 # 10% profit

    def __init__(self, cwicr_data: pd.DataFrame, overhead_rate: float = None, profit_rate: float = None, currency: str = "USD"): """Initialize calculator with CWICR data.""" self.data = cwicr_data self.overhead_rate = overhead_rate or self.DEFAULT_OVERHEAD_RATE self.profit_rate = profit_rate or self.DEFAULT_PROFIT_RATE self.currency = currency

    # Index data for fast lookup self._index_data()

    def _index_data(self): """Create index for fast work item lookup.""" if 'work_item_code' in self.data.columns: self._code_index = self.data.set_index('work_item_code') else: self._code_index = None

    def calculate_item_cost(self, work_item_code: str, quantity: float, price_overrides: Dict[str, float] = None) -> CostBreakdown: """Calculate cost for single work item."""

    # Find work item in database if self._code_index is not None and work_item_code in self._code_index.index: item = self._code_index.loc[work_item_code] else: # Try partial match matches = self.data[ self.data['work_item_code'].str.contains(work_item_code, case=False, na=False) ] if matches.empty: return CostBreakdown( work_item_code=work_item_code, description="NOT FOUND", unit="", quantity=quantity, status=CostStatus.MISSING_DATA ) item = matches.iloc[0]

    # Get base costs labor_unit = float(item.get('labor_cost', 0) or 0) material_unit = float(item.get('material_cost', 0) or 0) equipment_unit = float(item.get('equipment_cost', 0) or 0)

    # Apply price overrides if provided if price_overrides: if 'labor_rate' in price_overrides: labor_norm = float(item.get('labor_norm', 0) or 0) labor_unit = labor_norm * price_overrides['labor_rate'] if 'material_factor' in price_overrides: material_unit *= price_overrides['material_factor'] if 'equipment_factor' in price_overrides: equipment_unit *= price_overrides['equipment_factor']

    # Calculate component costs labor_cost = labor_unit * quantity material_cost = material_unit * quantity equipment_cost = equipment_unit * quantity

    # Direct costs direct_cost = labor_cost + material_cost + equipment_cost

    # Overhead and profit overhead_cost = direct_cost * self.overhead_rate profit_cost = (direct_cost + overhead_cost) * self.profit_rate

    # Total total_cost = direct_cost + overhead_cost + profit_cost

    # Unit price unit_price = total_cost / quantity if quantity > 0 else 0

    return CostBreakdown( work_item_code=work_item_code, description=str(item.get('description', '')), unit=str(item.get('unit', '')), quantity=quantity, labor_cost=labor_cost, material_cost=material_cost, equipment_cost=equipment_cost, overhead_cost=overhead_cost, profit_cost=profit_cost, unit_price=unit_price, total_cost=total_cost, labor_hours=float(item.get('labor_norm', 0) or 0) * quantity, labor_rate=float(item.get('labor_rate', 0) or 0), status=CostStatus.CALCULATED )

    def calculate_estimate(self, items: List[Dict[str, Any]], group_by_category: bool = True) -> CostSummary: """Calculate cost estimate for multiple items."""

    breakdowns = [] for item in items: code = item.get('work_item_code') or item.get('code') qty = item.get('quantity', 0) overrides = item.get('price_overrides')

    breakdown = self.calculate_item_cost(code, qty, overrides) breakdowns.append(breakdown)

    # Aggregate totals labor_total = sum(b.labor_cost for b in breakdowns) material_total = sum(b.material_cost for b in breakdowns) equipment_total = sum(b.equipment_cost for b in breakdowns) overhead_total = sum(b.overhead_cost for b in breakdowns) profit_total = sum(b.profit_cost for b in breakdowns) total_cost = sum(b.total_cost for b in breakdowns)

    # Group by category if requested breakdown_by_category = {} if group_by_category: for b in breakdowns: # Extract category from work item code prefix category = b.work_item_code.split('-')[0] if '-' in b.work_item_code else 'Other' if category not in breakdown_by_category: breakdown_by_category[category] = 0 breakdown_by_category[category] += b.total_cost

    return CostSummary( total_cost=total_cost, labor_total=labor_total, material_total=material_total, equipment_total=equipment_total, overhead_total=overhead_total, profit_total=profit_total, item_count=len(breakdowns), currency=self.currency, calculated_at=datetime.now(), breakdown_by_category=breakdown_by_category )

    def calculate_from_qto(self, qto_df: pd.DataFrame, code_column: str = 'work_item_code', quantity_column: str = 'quantity') -> pd.DataFrame: """Calculate costs from Quantity Takeoff DataFrame."""

    results = [] for _, row in qto_df.iterrows(): code = row[code_column] qty = row[quantity_column]

    breakdown = self.calculate_item_cost(code, qty) result = breakdown.to_dict()

    # Add original QTO columns for col in qto_df.columns: if col not in result: result[f'qto_{col}'] = row[col]

    results.append(result)

    return pd.DataFrame(results)

    def apply_regional_factors(self, base_costs: pd.DataFrame, region_factors: Dict[str, float]) -> pd.DataFrame: """Apply regional adjustment factors.""" adjusted = base_costs.copy()

    if 'labor_cost' in adjusted.columns and 'labor' in region_factors: adjusted['labor_cost'] *= region_factors['labor']

    if 'material_cost' in adjusted.columns and 'material' in region_factors: adjusted['material_cost'] *= region_factors['material']

    if 'equipment_cost' in adjusted.columns and 'equipment' in region_factors: adjusted['equipment_cost'] *= region_factors['equipment']

    # Recalculate totals adjusted['direct_cost'] = ( adjusted.get('labor_cost', 0) + adjusted.get('material_cost', 0) + adjusted.get('equipment_cost', 0) ) adjusted['total_cost'] = adjusted['direct_cost'] * (1 + self.overhead_rate) * (1 + self.profit_rate)

    return adjusted

    def compare_estimates(self, estimate1: CostSummary, estimate2: CostSummary) -> Dict[str, Any]: """Compare two cost estimates.""" return { 'total_difference': estimate2.total_cost - estimate1.total_cost, 'total_percent_change': ( (estimate2.total_cost - estimate1.total_cost) / estimate1.total_cost * 100 if estimate1.total_cost > 0 else 0 ), 'labor_difference': estimate2.labor_total - estimate1.labor_total, 'material_difference': estimate2.material_total - estimate1.material_total, 'equipment_difference': estimate2.equipment_total - estimate1.equipment_total, 'item_count_difference': estimate2.item_count - estimate1.item_count }

    class CostReportGenerator: """Generate cost reports from calculations."""

    def __init__(self, calculator: CWICRCostCalculator): self.calculator = calculator

    def generate_summary_report(self, items: List[Dict[str, Any]]) -> Dict[str, Any]: """Generate summary cost report.""" summary = self.calculator.calculate_estimate(items)

    return { 'report_date': datetime.now().isoformat(), 'currency': summary.currency, 'total_cost': round(summary.total_cost, 2), 'breakdown': { 'labor': round(summary.labor_total, 2), 'material': round(summary.material_total, 2), 'equipment': round(summary.equipment_total, 2), 'overhead': round(summary.overhead_total, 2), 'profit': round(summary.profit_total, 2) }, 'percentages': { 'labor': round(summary.labor_total / summary.total_cost * 100, 1) if summary.total_cost > 0 else 0, 'material': round(summary.material_total / summary.total_cost * 100, 1) if summary.total_cost > 0 else 0, 'equipment': round(summary.equipment_total / summary.total_cost * 100, 1) if summary.total_cost > 0 else 0, }, 'item_count': summary.item_count, 'by_category': summary.breakdown_by_category }

    def generate_detailed_report(self, items: List[Dict[str, Any]]) -> pd.DataFrame: """Generate detailed line-item report.""" results = []

    for item in items: code = item.get('work_item_code') or item.get('code') qty = item.get('quantity', 0)

    breakdown = self.calculator.calculate_item_cost(code, qty) results.append(breakdown.to_dict())

    df = pd.DataFrame(results)

    # Add totals row totals = df[['labor_cost', 'material_cost', 'equipment_cost', 'overhead_cost', 'profit_cost', 'total_cost']].sum() totals['description'] = 'TOTAL' totals['work_item_code'] = ''

    df = pd.concat([df, pd.DataFrame([totals])], ignore_index=True)

    return df

    Convenience functions

    def calculate_cost(cwicr_data: pd.DataFrame, work_item_code: str, quantity: float) -> float: """Quick cost calculation.""" calc = CWICRCostCalculator(cwicr_data) breakdown = calc.calculate_item_cost(work_item_code, quantity) return breakdown.total_cost

    def estimate_project_cost(cwicr_data: pd.DataFrame, items: List[Dict[str, Any]]) -> Dict[str, Any]: """Quick project cost estimate.""" calc = CWICRCostCalculator(cwicr_data) report = CostReportGenerator(calc) return report.generate_summary_report(items)