Substrate/Data/US-Inflation/source.md

# U.S. Consumer Price Index (CPI-U) - Inflation Time Series

**Source ID:** DS-00003
**Record Created:** 2025-10-25
**Last Updated:** 2025-10-25
**Cataloger:** Substrate Data Curation
**Review Status:** Reviewed

---

## Bibliographic Information

### Title Statement
- **Main Title:** Consumer Price Index for All Urban Consumers: All Items in U.S. City Average (CPIAUCSL)
- **Subtitle:** Monthly U.S. Inflation Measure, Seasonally Adjusted (1947-Present)
- **Abbreviated Title:** CPI-U, CPIAUCSL
- **Variant Titles:** U.S. CPI, Consumer Price Index, Inflation Index, CPI All Items

### Responsibility Statement
- **Publisher/Issuing Body:** Federal Reserve Bank of St. Louis (FRED)
- **Department/Division:** Federal Reserve Economic Data (FRED) Division
- **Contributors:** Bureau of Labor Statistics (BLS - primary source), U.S. Department of Labor
- **Contact Information:** stlsFRED@stls.frb.org

### Publication Information
- **Place of Publication:** St. Louis, Missouri, USA (FRED); Washington, D.C., USA (BLS)
- **Date of First Publication:** 1947-01 (monthly series)
- **Publication Frequency:** Monthly (released mid-month, typically day 12-15)
- **Current Status:** Active

### Edition/Version Information
- **Current Version:** Continuous monthly updates
- **Version History:** 1947-present continuous series; base period re-anchored periodically (current: 1982-1984 = 100)
- **Versioning Scheme:** Monthly releases with minimal historical revisions

---

## Authority Statement

### Organizational Authority

**Issuing Organization Analysis:**
- **Official Name:** Federal Reserve Bank of St. Louis (FRED aggregator); Bureau of Labor Statistics (BLS - primary authority)
- **Type:** Federal Reserve Bank (FRED); Federal Government Statistical Agency (BLS)
- **Established:** FRED: 1991; BLS: 1884 (140+ years of labor statistics)
- **Mandate:** Federal Reserve Act (FRED); Bureau of Labor Statistics Act - authority to measure labor market conditions and price changes
- **Parent Organization:** Federal Reserve System (FRED); U.S. Department of Labor (BLS)
- **Governance Structure:** Federal Reserve Bank board (FRED); Presidential appointment + Senate confirmation (BLS Commissioner)

**Domain Authority:**
- **Subject Expertise:** Price measurement, inflation statistics (BLS 140+ years); economic data aggregation (FRED 30+ years)
- **Recognition:** BLS is U.S. principal statistical agency for labor and price statistics; CPI is the most widely-used inflation measure globally
- **Publication History:** CPI published since 1913 (various forms), continuous monthly since 1947; FRED since 1991
- **Peer Recognition:** Federal Reserve, Treasury, Social Security Administration, academic economists worldwide cite BLS CPI

**Quality Oversight:**
- **Peer Review:** BLS methodology reviewed by National Academy of Sciences, academic economists (Boskin Commission, others)
- **Editorial Board:** Technical Advisory Committee on the Consumer Price Index
- **Scientific Committee:** Bureau of Labor Statistics leadership (professional economists and statisticians)
- **External Audit:** Subject to Government Accountability Office (GAO) oversight
- **Certification:** Follows international standards (ILO CPI Manual, UN Statistical Commission)

**Independence Assessment:**
- **Funding Model:** Federal appropriations (no commercial interests)
- **Political Independence:** Professional statistical agency; BLS Commissioner serves under civil service protections; statutory independence
- **Commercial Interests:** None (federal government mission)
- **Transparency:** Complete methodology documentation (BLS Handbook of Methods); data collection procedures published

### Data Authority

**Provenance Classification:**
- **Source Type:** Primary (BLS direct measurement from price collection)
- **Data Origin:** BLS collects ~80,000 price quotes monthly from ~23,000 retail and service establishments across 75 urban areas
- **Chain of Custody:** Price collectors → BLS field offices → National office aggregation → Statistical analysis → FRED aggregation → Public access

**Primary Source Characteristics:**
- BLS is the authoritative U.S. statistical agency for CPI compilation
- Direct measurement from retail prices (in-person and online price collection)
- Legal mandate under Bureau of Labor Statistics Act
- Follows internationally-recognized Consumer Price Index methodology (ILO CPI Manual)

---

## Scope Note

### Content Description

**Subject Coverage:**
- **Primary Subjects:** Inflation, Price Indices, Cost of Living, Consumer Economics
- **Secondary Subjects:** Macroeconomics, Monetary Policy, Purchasing Power, Real Value Adjustments
- **Subject Classification:**
  - LC: HB (Economic Theory), HC (Economic History and Conditions)
  - Dewey: 338.5 (Prices), 330.973 (U.S. Economics)
- **Keywords:** CPI, Consumer Price Index, inflation, price index, purchasing power, cost of living, real wages, deflator, basket of goods, seasonally adjusted

**Geographic Coverage:**
- **Spatial Scope:** United States (75 urban areas covering ~93% of U.S. population)
- **Countries/Regions Included:** United States only (separate CPI series exist for regions)
- **Geographic Granularity:** National aggregate (separate metropolitan area CPIs available)
- **Coverage Completeness:** 93% of U.S. population (all urban consumers)
- **Notable Exclusions:** Rural populations (~7% of U.S.), military personnel, institutionalized populations

**Temporal Coverage:**
- **Start Date:** 1947-01 (monthly series); 1913 (earlier annual series)
- **End Date:** Present (ongoing monthly updates)
- **Historical Depth:** 78+ years (monthly), 112+ years (including earlier series)
- **Frequency of Observations:** Monthly
- **Temporal Granularity:** Month-level
- **Time Series Continuity:** Excellent; continuous monthly data with minimal revisions

**Population/Cases Covered:**
- **Target Population:** All urban consumers (~93% of U.S. population)
- **Inclusion Criteria:** Expenditure patterns of urban wage earners, clerical workers, professional, managerial, technical workers, self-employed, unemployed, retirees
- **Exclusion Criteria:** Rural non-metropolitan populations, farm families, military on base, institutionalized persons
- **Coverage Rate:** 93% of U.S. total population
- **Sample vs. Census:** Sample-based: ~23,000 retail establishments, ~80,000 price quotes monthly

**Variables/Indicators:**
- **Number of Variables:** 1 primary series (CPIAUCSL); 8,000+ related detailed CPI series
- **Core Indicators:**
  - CPI Index (1982-1984 = 100 baseline)
  - Month-over-month change
  - Year-over-year inflation rate
  - Seasonally adjusted values
- **Derived Variables:** Inflation rates (monthly, annual), real wage deflators, purchasing power calculations
- **Data Dictionary Available:** Yes - BLS CPI Handbook of Methods

### Content Boundaries

**What This Source IS:**
- Gold-standard measure of U.S. consumer price inflation
- Primary indicator used by Federal Reserve for monetary policy (2% inflation target)
- Official U.S. government price statistic for cost-of-living adjustments (Social Security, tax brackets)
- Internationally-comparable using ILO CPI Manual framework
- Best source for understanding U.S. purchasing power changes over time

**What This Source IS NOT:**
- NOT a cost-of-living index (does not account for substitution, quality changes perfectly)
- NOT a measure of prices paid by businesses (use Producer Price Index)
- NOT adjusted for individual consumption patterns (measures average urban consumer)
- NOT real-time (2-week lag from month end to publication)
- NOT granular below national level (use metropolitan area CPIs for local analysis)

**Comparison with Similar Sources:**

| Source | Advantages Over This Source | Disadvantages vs. This Source |
|--------|----------------------------|-------------------------------|
| PCE Price Index (Fed preferred) | Accounts for consumer substitution; broader coverage | Less widely known; more complex methodology |
| CPI-W (Urban Wage Earners) | Specific to wage/clerical workers | Narrower coverage (32% of population vs 93%) |
| Chained CPI | Better accounts for substitution | More complex; less historical data |
| PPI (Producer Price Index) | Business/wholesale prices | Not consumer-facing; different concept |

---

## Access Conditions

### Technical Access

**API Information:**
- **Endpoint URL:** https://fred.stlouisfed.org/graph/fredgraph.csv?id=CPIAUCSL&cosd=1947-01-01
- **API Type:** Direct CSV download (HTTP GET); also FRED API available
- **API Version:** FRED API v1
- **OpenAPI/Swagger Spec:** https://fred.stlouisfed.org/docs/api/fred/
- **SDKs/Libraries:** Python (fredapi), R (fredr), unofficial libraries for other languages

**Authentication:**
- **Authentication Required:** No (for CSV); Yes for FRED API
- **Authentication Type:** API Key (free) for FRED API
- **Registration Process:** Sign up at https://fredaccount.stlouisfed.org/apikeys
- **Approval Required:** No (instant API key)
- **Approval Timeframe:** Immediate

**Rate Limits:**
- **Requests per Second:** Not documented for CSV download; reasonable use expected
- **Requests per Day:** FRED API: 120 requests/minute
- **Concurrent Connections:** Not specified
- **Throttling Policy:** API enforces rate limits with 429 status code
- **Rate Limit Headers:** Not provided for CSV; API includes rate limit info

**Query Capabilities:**
- **Filtering:** CSV downloads full series; FRED API supports date range filtering
- **Sorting:** Chronological (inherent in time series)
- **Pagination:** Not applicable (full series download)
- **Aggregation:** Pre-aggregated monthly data
- **Joins:** Not applicable (single time series)

**Data Formats:**
- **Available Formats:** CSV (direct download), JSON/XML (FRED API)
- **Format Quality:** Well-formed CSV; UTF-8 encoded; consistent schema
- **Compression:** Not compressed
- **Encoding:** UTF-8

**Download Options:**
- **Bulk Download:** Yes - full CSV download
- **Streaming API:** No
- **FTP/SFTP:** No
- **Torrent:** No
- **Data Dumps:** Full series download each time (not incremental)

**Reliability Metrics:**
- **Uptime:** Very high (99.9%+ estimated); Federal Reserve infrastructure
- **Latency:** <1 second for CSV download
- **Breaking Changes:** Schema stable for decades; BLS methodology changes documented years in advance
- **Deprecation Policy:** Federal Reserve commitment to long-term data availability
- **Service Level Agreement:** No formal SLA (federal government service)

### Legal/Policy Access

**License:**
- **License Type:** Public Domain (U.S. Government Work)
- **License Version:** N/A
- **License URL:** https://www.usa.gov/government-works
- **SPDX Identifier:** CC0-1.0 (effectively public domain for U.S. government data)

**Usage Rights:**
- **Redistribution Allowed:** Yes (public domain)
- **Commercial Use Allowed:** Yes (public domain)
- **Modification Allowed:** Yes (public domain)
- **Attribution Required:** Not legally required; citation recommended as scholarly best practice
- **Share-Alike Required:** No

**Cost Structure:**
- **Access Cost:** Free

**Terms of Service:**
- **TOS URL:** https://fred.stlouisfed.org/legal/
- **Key Restrictions:** No restrictions (public domain); standard disclaimer
- **Liability Disclaimers:** Federal Reserve not liable for decisions based on data
- **Privacy Policy:** FRED collects website analytics; no personal data in economic statistics

---

## Collection Development Policy Fit

### Relevance Assessment

**Substrate Mission Alignment:**
- **Human Progress Focus:** Purchasing power and cost-of-living central to measuring economic wellbeing and human progress
- **Problem-Solution Connection:**
  - Links to Problems: Inflation volatility, wage erosion, economic inequality measurement
  - Links to Solutions: Monetary policy frameworks, real wage adjustments, retirement planning
- **Evidence Quality:** Gold-standard for U.S. inflation measurement; supports evidence-based economic analysis

**Collection Priorities Match:**
- **Priority Level:** CRITICAL - essential source for U.S. economic domain
- **Uniqueness:** Official U.S. government inflation measure; most widely-used price index
- **Comprehensiveness:** Fills critical gap; no other source provides this combination of authority, coverage, and historical depth

### Comparison with Holdings

**Overlapping Sources:**
- DS-00002: U.S. GDP (complementary - GDP for output, CPI for prices)
- Future: PCE Price Index (Federal Reserve's preferred inflation measure)

**Unique Contribution:**
- Official BLS/U.S. government price statistic
- Most widely-cited inflation measure (Social Security COLA, tax brackets)
- Longest consistent time series (1947-present monthly)
- Used for real value adjustments across all economic research

**Preferred Use Cases:**
- When official U.S. government inflation statistics required
- Historical inflation analysis (1947-present)
- Real wage and real value calculations
- Cost-of-living adjustment research
- Monetary policy analysis (Federal Reserve 2% target)

---

## Technical Specifications

### Data Model

**Schema Documentation:**
- **Schema Type:** CSV with defined column structure
- **Schema URL:** https://fred.stlouisfed.org/series/CPIAUCSL
- **Schema Version:** Stable since FRED inception

**Entity Types:**
- Monthly CPI observations (time series)

**Key Relationships:**
- Date → CPI Value

**Primary Keys:**
- Date (YYYY-MM-DD)

**Foreign Keys:**
- None (single time series)

### Metadata Standards Compliance

**Standards Followed:**
- [x] Dublin Core
- [x] DCAT (Data Catalog Vocabulary)
- [x] Schema.org Dataset
- [x] SDMX (Statistical Data and Metadata eXchange)
- [ ] DDI (Data Documentation Initiative) - minimal
- [ ] ISO 19115 (Geographic Information Metadata) - not applicable
- [ ] MARC
- Other: ILO CPI Manual methodology standards

**Metadata Quality:**
- **Completeness:** 90% of elements populated
- **Accuracy:** High - metadata maintained by FRED and BLS
- **Consistency:** Excellent - SDMX compliance ensures consistency

### API Documentation Quality

**Documentation Assessment:**
- **Completeness:** Comprehensive - all endpoints documented with examples
- **Examples Provided:** Yes - extensive examples in multiple programming languages
- **Error Messages:** Clear HTTP status codes and error descriptions
- **Change Log:** Maintained at https://fred.stlouisfed.org/docs/api/fred/
- **Tutorials:** Available - step-by-step guides for common tasks
- **Support Forum:** Email support stlsFRED@stls.frb.org; no public forum

---

## Source Evaluation Narrative

### Methodological Assessment

**Data Collection Methodology:**

**Sampling Design:**
- **Method:** Probability sample (scientifically-selected retail establishments and items)
- **Sample Size:** ~23,000 retail and service establishments; ~80,000 price quotes monthly
- **Sampling Frame:** Universe of U.S. urban retail establishments
- **Stratification:** By item category, geographic region, establishment type
- **Weighting:** Expenditure weights from Consumer Expenditure Survey (updated every 2 years)

**Data Collection Instruments:**
- **Instrument Type:** Direct price observation (in-person and online price collection)
- **Validation:** BLS field supervisors verify price quotes; automated consistency checks
- **Question Wording:** Standardized price collection protocols (exact item specifications)
- **Mode:** In-person visits (grocery, retail), phone (services), online (e-commerce)

**Quality Control Procedures:**
- **Field Supervision:** BLS regional offices supervise price collectors
- **Validation Rules:** Automated checks for price changes >10%; item substitution protocols
- **Consistency Checks:** Cross-validation across similar items and geographic areas
- **Verification:** Monthly review by BLS economists
- **Outlier Treatment:** Large price changes investigated and verified before inclusion

**Error Characteristics:**
- **Sampling Error:** Very low for national CPI (large sample); confidence intervals not published
- **Non-sampling Error:** Item substitution bias, quality adjustment challenges, new product introduction lag
- **Known Biases:** Upward bias (~0.5-1.0% annually) from substitution, quality changes (Boskin Commission findings)
- **Accuracy Bounds:** Academic estimates suggest ±0.1-0.3% for monthly CPI

**Methodology Documentation:**
- **Transparency Level:** 5/5 (Exemplary)
- **Documentation URL:** https://www.bls.gov/opub/hom/cpi/
- **Peer Review Status:** BLS methods reviewed by National Academy of Sciences; published in peer-reviewed journals
- **Reproducibility:** Methodology fully documented; data collection procedures published

### Currency Assessment

**Update Characteristics:**
- **Update Frequency:** Monthly (released mid-month, typically day 12-15)
- **Update Reliability:** Extremely consistent; releases follow strict schedule (8:30 AM ET)
- **Update Notification:** BLS release calendar published; FRED email alerts available
- **Last Updated:** 2025-08 (most recent as of October 2025)

**Timeliness:**
- **Collection to Publication Lag:** ~2 weeks (data for month M published mid-month M+1)
- **Factors Affecting Timeliness:** Price collection window, quality review process
- **Historical Timeliness:** Consistent monthly release schedule maintained for decades

**Currency for Different Uses:**
- **Real-time Analysis:** Unsuitable (2-week lag); most current available for monthly data
- **Recent Trends:** Excellent (monthly updates capture trends within 6 weeks)
- **Historical Research:** Excellent (continuous series 1947-present)

### Objectivity Assessment

**Potential Biases:**

**Political Bias:**
- **Government Influence:** Statistical agency independence protected by law; BLS Commissioner serves under civil service
- **Editorial Stance:** Professional statistical neutrality mandated by statute
- **Political Pressure:** Occasional political commentary on CPI methodology; independence maintained

**Commercial Bias:**
- **Funding Sources:** Federal appropriations (no commercial interests)
- **Advertising Influence:** Not applicable
- **Proprietary Interests:** None

**Cultural/Social Bias:**
- **Geographic Bias:** Urban-centric (excludes rural 7%); 75 urban areas weighted by population
- **Social Perspective:** Average consumer basket may not reflect low-income or high-income consumption
- **Language Bias:** Published in English; limited translation
- **Selection Bias:** Item selection based on Consumer Expenditure Survey (updated every 2 years)

**Transparency:**
- **Bias Disclosure:** BLS acknowledges known biases (substitution, quality adjustment); Boskin Commission documented
- **Limitations Stated:** Comprehensive methodology documentation notes limitations
- **Raw Data Available:** Detailed CPI components published; micro-data not publicly available (establishment confidentiality)

### Reliability Assessment

**Consistency:**
- **Internal Consistency:** Item-level CPIs aggregate mathematically to headline CPI
- **Temporal Consistency:** Stable methodology; major changes documented and phased in gradually
- **Cross-source Consistency:** Good agreement with PCE Price Index, IMF WEO inflation data

**Stability:**
- **Definition Changes:** Occasional - major methodology updates implemented gradually (e.g., geometric mean, hedonic quality adjustment)
- **Methodology Changes:** Well-documented; typically phased in over years
- **Series Breaks:** Clearly marked when major changes implemented (base period changes)

**Verification:**
- **Independent Verification:** Academic economists extensively study CPI; Boskin Commission independent review
- **Replication Studies:** Researchers use CPI data extensively; errors/discrepancies reported and corrected
- **Audit Results:** GAO audits BLS periodically; no major data quality issues identified

### Accuracy Assessment

**Validation Evidence:**
- **Benchmark Comparisons:** CPI compared to PCE Price Index (Federal Reserve preferred measure); differences documented
- **Coverage Assessments:** Expenditure weights updated from Consumer Expenditure Survey
- **Error Studies:** Boskin Commission (1996) estimated upward bias ~1.1% annually; BLS improvements reduced to ~0.5%

**Accuracy for Different Uses:**
- **Point Estimates:** Highly reliable for national monthly CPI (large sample)
- **Trend Analysis:** Excellent for medium-term trends (6+ months); month-to-month noise exists
- **Cross-sectional Comparison:** Not applicable (U.S. only); international comparisons use Harmonized Indices
- **Sub-population Analysis:** Limited - metropolitan area CPIs available; no income-specific CPIs

---

## Known Limitations and Caveats

### Coverage Limitations

**Geographic Gaps:**
- Rural non-metropolitan areas (~7% of U.S. population)
- Alaska and Hawaii covered separately (not in national index)

**Temporal Gaps:**
- No gaps in monthly series since 1947
- Earlier data (1913-1946) less frequent or different methodology

**Population Exclusions:**
- Rural populations
- Military personnel on base
- Institutionalized populations (prisons, nursing homes)

**Variable Gaps:**
- No individual consumption pattern adjustments (average consumer only)
- No wealth or asset price changes (home prices, stocks)
- Services quality changes challenging to capture

### Methodological Limitations

**Sampling Limitations:**
- Item substitution when products discontinued (introduces quality adjustment challenges)
- New products introduced with lag (e.g., smartphones took years to enter basket)

**Measurement Limitations:**
- Quality improvements difficult to separate from price increases (hedonic quality adjustment imperfect)
- Online prices increasingly important; methodology adapting
- Shrinkflation (smaller package size for same price) challenging to capture

**Processing Limitations:**
- Seasonal adjustment can mask underlying trends
- Base period changes (1982-1984 = 100) require careful interpretation for long-term comparisons

### Comparability Limitations

**Cross-national Comparability:**
- Different countries use different CPI methodologies
- Harmonized Index of Consumer Prices (HICP) used for international comparisons

**Temporal Comparability:**
- Methodology improvements over time (geometric mean, hedonic quality, internet prices)
- Base period re-anchored periodically (does not affect inflation rates, but index levels)

**Sub-group Comparability:**
- No income-specific CPIs (average consumer only)
- Metropolitan area CPIs exist but smaller samples (wider confidence intervals)

### Usage Caveats

**Inappropriate Uses:**
1. **DO NOT use for individual consumption** - reflects average urban consumer, not personal basket
2. **DO NOT use as cost-of-living index** - does not fully account for substitution or quality
3. **DO NOT compare month-to-month** without considering seasonal patterns and noise
4. **DO NOT use for asset prices** - excludes home prices, stocks, bonds (use Case-Shiller, S&P500)

**Ecological Fallacy Risks:**
- National CPI does not reflect individual cities (use metropolitan CPIs)
- Average CPI does not reflect low-income or high-income consumption patterns

**Correlation vs. Causation:**
- CPI measures price changes, not causes of inflation
- Appropriate for descriptive analysis, not causal inference without economic models

---

## Recommended Use Cases

### Ideal Applications

**Research Questions Well-Suited:**
1. "How has U.S. purchasing power changed over the past 50 years?"
2. "What is the real (inflation-adjusted) return on investment?"
3. "How does wage growth compare to inflation?"
4. "What is the Federal Reserve's progress toward 2% inflation target?"

**Analysis Types Supported:**
- Descriptive statistics (inflation rates over time)
- Trend analysis (long-term inflation patterns)
- Real value adjustments (converting nominal to real dollars)
- Policy evaluation (Federal Reserve inflation targeting)

### Appropriate Contexts

**Geographic Contexts:**
- U.S. national analysis
- Cross-country comparisons (with Harmonized Indices or equivalent)

**Temporal Contexts:**
- Long-term trends (1947-present)
- Historical research (especially post-WWII era)
- Month-to-month changes (with seasonal adjustment consideration)

**Subject Contexts:**
- Purchasing power analysis
- Real wage calculations
- Retirement planning (Social Security COLA)
- Economic policy evaluation

### Use Warnings

**Avoid Using This Source For:**
1. **Individual consumption patterns** → Use personal budget tracking
2. **Real estate price inflation** → Use Case-Shiller Home Price Index
3. **Asset price changes** → Use stock indices, bond yields
4. **Immediate/real-time inflation** → Use high-frequency alternative data (Billion Prices Project)
5. **Rural cost of living** → No rural CPI available

**Recommended Alternatives For:**
- Federal Reserve policy → PCE Price Index (Fed's preferred measure)
- Producer/wholesale prices → Producer Price Index (PPI)
- Import/export prices → Import/Export Price Indices
- Wage earner specific → CPI-W (Urban Wage Earners and Clerical Workers)

---

## Citation

### Preferred Citation Format

**APA 7th:**
U.S. Bureau of Labor Statistics. (2025). *Consumer Price Index for All Urban Consumers: All Items in U.S. City Average* [CPIAUCSL]. Federal Reserve Bank of St. Louis. Retrieved October 25, 2025, from https://fred.stlouisfed.org/series/CPIAUCSL

**Chicago 17th:**
U.S. Bureau of Labor Statistics. "Consumer Price Index for All Urban Consumers: All Items in U.S. City Average (CPIAUCSL)." Federal Reserve Bank of St. Louis, FRED. Accessed October 25, 2025. https://fred.stlouisfed.org/series/CPIAUCSL.

**MLA 9th:**
U.S. Bureau of Labor Statistics. *Consumer Price Index for All Urban Consumers: All Items in U.S. City Average*. FRED, Federal Reserve Bank of St. Louis, 2025, fred.stlouisfed.org/series/CPIAUCSL.

**Vancouver:**
U.S. Bureau of Labor Statistics. Consumer Price Index for All Urban Consumers: All Items in U.S. City Average (CPIAUCSL) [Internet]. St. Louis: Federal Reserve Bank of St. Louis, FRED; 2025 [cited 2025 Oct 25]. Available from: https://fred.stlouisfed.org/series/CPIAUCSL

**BibTeX:**
```bibtex
@misc{bls_cpi_2025,
  author = {{U.S. Bureau of Labor Statistics}},
  title = {Consumer Price Index for All Urban Consumers: All Items in U.S. City Average (CPIAUCSL)},
  year = {2025},
  publisher = {Federal Reserve Bank of St. Louis, FRED},
  url = {https://fred.stlouisfed.org/series/CPIAUCSL},
  note = {Accessed: 2025-10-25}
}
```

### Data Citation Principles

Following FORCE11 Data Citation Principles:
- **Importance:** CPI is citable research output; cite in publications using inflation-adjusted values
- **Credit and Attribution:** Citations credit BLS for data collection, FRED for aggregation
- **Evidence:** Citations enable readers to verify inflation adjustments
- **Unique Identification:** FRED series ID (CPIAUCSL) + access date for exact reproducibility
- **Access:** Citation provides direct access method (URL)
- **Persistence:** FRED maintains stable URLs; archived through Internet Archive
- **Specificity and Verifiability:** Series ID and date range ensure exact reproducibility
- **Interoperability:** Citation format compatible with reference managers
- **Flexibility:** Adaptable to various research outputs

---

## Version History

### Current Version
- **Version:** Continuous monthly series
- **Date:** 1947-01 to present
- **Changes:** Monthly additions; base period 1982-1984 = 100

### Previous Versions
- **Base Period Changes:** 1967 = 100 (historical), 1982-1984 = 100 (current)

---

## Review Log

### Internal Reviews
- **Date:** 2025-10-25 | **Reviewer:** Substrate Data Curation | **Status:** Approved | **Notes:** Initial catalog entry; comprehensive evaluation completed

### Quality Checks
- **Last Metadata Validation:** 2025-10-25
- **Last Authority Verification:** 2025-10-25
- **Last Link Check:** 2025-10-25
- **Last Access Test:** 2025-10-25 (CSV download tested successfully)

---

## Related Resources

### Cross-References

**Related Substrate Entities:**
- **Problems:**
  - Inflation volatility
  - Wage erosion
  - Cost-of-living measurement
- **Solutions:**
  - Monetary policy frameworks
  - Index-linked financial instruments
  - Real wage adjustments
- **Organizations:**
  - Bureau of Labor Statistics
  - Federal Reserve System
  - Federal Reserve Bank of St. Louis
- **Other Data Sources:**
  - DS-00002: U.S. GDP (Real GDP for output measurement)
  - Future: PCE Price Index (Federal Reserve's preferred inflation measure)

**External Resources:**
- **Alternative Sources:**
  - PCE Price Index: https://fred.stlouisfed.org/series/PCEPI
  - Producer Price Index: https://www.bls.gov/ppi/
- **Complementary Sources:**
  - Consumer Expenditure Survey: https://www.bls.gov/cex/
  - Real Earnings: https://www.bls.gov/news.release/realer.htm
- **Source Comparison Studies:**
  - Boskin Commission Report (1996): "Toward a More Accurate Measure of the Cost of Living"
  - Academic research on CPI vs. PCE differences

### Additional Documentation

**User Guides:**
- BLS CPI Home Page: https://www.bls.gov/cpi/
- FRED Series Page: https://fred.stlouisfed.org/series/CPIAUCSL

**Research Using This Source:**
- Millions of citations in economic research
- Federal Reserve policy analysis
- Social Security COLA calculations

**Methodology Papers:**
- BLS Handbook of Methods, Chapter 17 (Consumer Price Index)
- Boskin Commission Report (1996)

---

## Cataloger Notes

**Internal Notes:**
- Excellent source; highest authority; essential for Substrate economic domain
- CSV download simple and reliable
- Consider adding PCE Price Index as complement (Federal Reserve's preferred measure)
- CPI-W (wage earners) available as alternative series if needed

**To Do:**
- [ ] Add related organizations (BLS, Federal Reserve)
- [ ] Cross-reference with relevant Problems and Solutions
- [ ] Consider adding metropolitan area CPIs for geographic granularity

**Questions for Review:**
- Should we catalog PCE Price Index separately?
- How to handle base period changes in long-term analysis documentation?

---

**END OF SOURCE RECORD**