Authenticate and query BLS Occupational Employment and Wage Statistics (OEWS) data via the BLS Public Data API for SOC-level wage benchmarking

Steps

1. Register for a BLS API key at https://data.bls.gov/registrationEngine/ to increase the daily request limit from 25 (unauthenticated) to 500 series per day
2. Construct an OES series ID using the pattern: OESM{area_code}{industry_code}{occupation_code}{datatype_code}; e.g., OESM000000000000015-1252008 returns national all-industry annual mean wage for SOC 15-1252
3. POST to https://api.bls.gov/publicAPI/v2/timeseries/data/ with JSON body: {"seriesid": ["OESM..."], "startyear": "2023", "endyear": "2024", "registrationkey": "YOUR_KEY"}
4. Parse the response: data array contains year, period (A01 for annual), value (wage in dollars), and footnotes array; footnote code W indicates the estimate has been withheld
5. Retrieve area-specific wage data by replacing the area code: 0000000 is national; use CBSA codes (from BLS area definitions) for metropolitan area wages relevant to apprenticeship wage schedules
6. Cross-reference retrieved SOC wage percentiles (10th, 25th, median, 75th, 90th) against apprenticeship program wage schedules to verify compliance with prevailing wage requirements