Health Care and Social Assistance (U.S.) — NAICS 62 Sector Primer

A Histometrics rollup primer for a general investing audience — relevant to both public-market and private investors. NAICS (the North American Industry Classification System) is the U.S. government's standard scheme for grouping businesses by activity. This page covers the two-digit sector 62 — the top of the health-and-social-care branch of the economy — which contains four three-digit subsectors: ambulatory (outpatient) care (621), hospitals (622), nursing and residential care (623), and social assistance (624). It synthesizes the four already-written subsector primers and adds our ground-truth federal statistics for the combined sector; it does not re-research from scratch.

1. Overview

NAICS 62 is where America delivers care — medical and social — to people who need it: the doctor's office and the operating room, the nursing home and the assisted-living apartment, the food bank and the day-care center. It is the single largest employing sector in the United States, with about 22.1 million paid workers — on the order of one in every seven American jobs — spread across roughly 1.0 million establishments, generating about $3.33 trillion of measured receipts (revenue) and $1.39 trillion of annual payroll [1]. No other two-digit NAICS sector employs as many people.

But 62 is not one market you can buy — it is a bracket holding four very different subsectors that share a mission (care) and a cost base (people) but little else. They run on unlike economic engines, answer to different regulators, are owned by wildly different mixes (public companies, insurers, private equity, nonprofits, governments, and hundreds of thousands of small independents), and offer investors radically uneven ways in. Two of the four children — outpatient care (621) and hospitals (622) — are the "medical" half and together account for about 83% of the sector's revenue; the other two — residential care (623) and social assistance (624) — are the "care-and-social" half, only ~17% of revenue but ~32% of the jobs, because they are the most hands-on and least capital-intensive work in the sector.

The distinctive value of a sector view, then, is the contrast across the four children (Section 2): which are big, which way they are moving, who owns them, how concentrated they are, and how (if at all) an outsider can get exposure. A handful of threads tie the whole sector together — an aging, chronically ill population; a government (Medicare and Medicaid) that pays most of the bills; labor as the binding constraint everywhere; and the decades-long site-of-care shift that keeps moving treatment out of expensive hospitals into cheaper outpatient and home settings. Sections 3–10 treat the sector as a whole. Throughout, acronyms are defined on first use, and tickers, yields, and multiples are reserved for the investable-universe and how-to-invest sections.

2. What's inside — the four children, and how they differ

NAICS 62 splits into four three-digit subsectors. The table below is the heart of this primer; it is ordered by revenue, largest first. (Acronyms are defined in the note beneath the table and again on first substantive use in later sections.)

Notes. Shares are of the sector's 2022 receipts and 2023 employment (Section 3). PE = private equity; REIT = real estate investment trust (a landlord that owns the buildings and leases them to operators); "payvider" = a health insurer (payer) that also owns care providers; CCRC = continuing-care retirement community. The two largest children (ambulatory and hospitals) are nearly tied on revenue at ~42% each; the two smaller children (residential care and social assistance) are nearly tied at ~8.5% each. Tickers are identifiers, not recommendations, and are defined in Sections 4 and 10.

How to read the contrast. Four cuts matter most to an investor:

• Revenue splits into halves; employment does not. The two medical children (621 + 622) are ~83% of the sector's revenue but ~68% of its jobs; the two social/residential children (623 + 624) are only ~17% of revenue but ~32% of the jobs. That gap is the fingerprint of a capital-and-billing intensity gradient: hospitals earn ~$214,000 of revenue per worker (equipment- and facility-heavy), ambulatory ~$162,000, residential care ~$86,000, and social assistance ~$75,000 (the purest labor-for-time work). The more hands-on the caregiving, the more people it takes per dollar.
• Who pays is mostly the government — with one real exception. Medicare (federal insurance for people 65+ and some disabled) and Medicaid (joint federal-state insurance for low-income and disabled people), plus other public budgets, pay the majority of the sector. The patient or client rarely pays the bill directly. The exceptions are narrow and important: child care tuition (inside 624), private-pay senior living (inside 623), and elective dental, cosmetic, and wellness care (inside 621) — and those are exactly where the cleanest private-market economics and listed pure-plays sit.
• "Who owns it" spans the entire ownership spectrum — from tax-funded government (public hospitals, county mental-health clinics, municipal ambulance, state developmental centers), through non-tradable nonprofits (Kaiser, most large hospital systems, most retirement communities, food banks, Goodwill), to a fragmented base of clinician- and family-owners, up to PE roll-ups and, at the very top, a few vertically integrated insurers. No other sector of the economy mixes so many owner types under one code.
• The children are not moving together. Ambulatory care and the aging-driven home-care core are structural growth stories; hospital inpatient volume is flat-to-declining as care leaks out; senior living has the strongest demographic tailwind and pricing power; child care is boxed in by an affordability ceiling and an expired federal funding stream. A single "health-care and social-assistance" forecast would be wrong for at least one child.

3. Size — the sector as a whole

Our ground-truth federal figures for NAICS 62. Note the reference-year split: receipts, firms, and concentration are from the 2022 Economic Census (EC); establishments, employment, and payroll are from 2023 County Business Patterns (CBP). These are two different federal programs and two different years — do not read 2022 receipts against 2023 payroll as a margin.

How the children add up — a clean check on the data:

Establishments sum to the sector total exactly (1,003,398). Employment sums to 22,063,260 against the reported 22,063,238 — a 22-worker whisker that is pure rounding on the approximate hospital figure. Receipts sum to ~$3,329.9B against $3,330.3B, and annual payroll to ~$1,394.75B against $1,394.72B — both within rounding. Firm counts sum to ~696,500 against the sector's 691,347 — about 5,200 higher, exactly as expected, because a company that operates in two subsectors (a system that runs both hospitals and outpatient clinics; a platform in both home care and disability services) is counted in each child but only once at the sector level [1].

A few shape statistics for the sector:

• ~$4.82 million of receipts per firm and ~22 employees per establishment — an average that hides enormous variance, from a 1,000-employee hospital to a two-person doctor's office or a six-bed group home.
• ~$63,200 average annual pay and payroll at ~42% of receipts (across the vintage mismatch) — the fingerprint of a labor-heavy service sector whose scarce input is licensed clinicians and low-wage caregivers, not hard assets or brands.
• Revenue per worker diverges sharply by child — highest in hospitals (~$214,000, capital-and-billing-heavy) and ambulatory (~$162,000), lowest in social assistance (~$75,000) and residential care (~$86,000). The medical half earns more per worker; the social half employs more people per dollar.

The sector versus national health spending. Treat the $3.33 trillion as a floor for the care-delivery-and-social-services economy, not a health-spending total. It is neither. National health expenditure (NHE) was about $4.9 trillion in 2023, but the two measures are not comparable: NHE counts retail drugs, medical devices, and insurance administration that are coded outside sector 62 (pharmacies and insurers live in other NAICS sectors), while sector 62 includes the non-medical social-assistance work (food, housing, child care) that NHE largely excludes [6]. For orientation, hospital care ran ~$1.5 trillion, physician and clinical services ~$978 billion, and nursing-care facilities ~$211 billion in 2023 — all consistent with, but not identical to, the subsector receipts above [6].

The aggregation trap — the single most important caveat at this level. Read literally, sector 62 looks like near-perfect competition: an HHI (the sum of squared market shares antitrust regulators use, where anything under 1,500 is "unconcentrated") of just 10.4, and the four largest firms holding only 4.4% of revenue [1]. That number is real but deeply deceptive. Blending four subsectors whose market leaders don't overlap — the biggest hospital system, the biggest dialysis company, the biggest nursing-home operator, and the biggest child-care chain are all different firms — mechanically dilutes every company's share. The blended 10.4 lands near ambulatory's own low figure (10.3) rather than collapsing further only because the two giant medical children carry most of the weight; it sits far below hospitals' 34.4 and hides real dominance beneath it: a metro where one or two hospital systems control the entire inpatient market, a two-company dialysis duopoly, two national labs holding roughly a third of lab revenue [2][3]. Never read the sector HHI as evidence the market is competitive. Concentration in health care is local, and it is invisible in a national two-digit blend — judge it child by child, and inside the big children, market by market.

Undercount caveats — the sector understates its true footprint. These are employer-only counts: CBP and the Economic Census exclude the self-employed, no-payroll ("nonemployer") businesses, and most government-run establishments [1]. The gap is unusually large here because every child skews toward small, individually owned, nonprofit, or government operators:

• Solo clinicians and tiny operators are largely invisible — cash-only therapists, single-doctor practices, home-based family child care (market researchers count ~600,000 U.S. child-care businesses against ~82,000 employer establishments the Census sees) [2][5].
• Government and nonprofit care spills into other codes or off the books. Hospitals are a deliberate CBP exception — the employment and payroll figures do include public hospitals — but the Economic Census largely excludes government hospitals, so the $1.357 trillion hospital receipts (and therefore the sector's $3.33 trillion) are undercounts that miss the entire public hospital system [3]. Municipal ambulance, county mental-health clinics, state developmental centers, VA/military outpatient sites, and family members paid through Medicaid to care for a relative are mostly excluded as well [2][4][5].
• Donated goods and volunteer labor — the real "product" of the food-and-relief safety net — never touch payroll [5].

Our ground-truth file provides no sector-wide figure for payer mix, utilization, occupancy, margin, or nonemployer receipts, and no growth series — so none is asserted here. Treat the $3.33 trillion and ~1.0 million establishments as a solid floor for the employer-based care economy, never as a full census of the activity, and never as evidence the field is competitively structured.

4. The investable universe — where value concentrates across the children

Public-market value is not spread across sector 62 in proportion to revenue. There is no exchange-traded fund (ETF) and no clean public proxy for the sector as a whole, and vast stretches of it — most hospital capacity, the nonprofit and government majority of residential and social care, and hundreds of thousands of small practices — are not investable through equities at all. Where the listed exposure clusters:

• For-profit hospital chains (inside 622). HCA Healthcare (the scale leader), Tenet Healthcare (THC), Universal Health Services (UHS), Community Health Systems (CYH), and Ardent Health — a handful of stocks representing a small for-profit slice of an overwhelmingly nonprofit/government subsector [3].
• Ambulatory pure-plays (inside 621) — narrow and concentrated. Dialysis (DaVita (DVA), Fresenius Medical Care (FMS)), outpatient surgery (Surgery Partners (SGRY)), and the lab majors (Quest Diagnostics (DGX), Labcorp (LH)), plus rehab and mental-health operators — the cleanest listed exposure in the whole sector, but confined to capital-heavy corners [2].
• Health-care REITs (spanning 623 and parts of 622). The single cleanest way into the residential-care and hospital real estate: seniors-housing and skilled-nursing landlords Welltower (WELL), Ventas (VTR), Healthpeak (DOC), Omega Healthcare (OHI), CareTrust (CTRE), plus hospital landlord Medical Properties Trust (MPW) — you own the buildings and earn rent, not the operating company [3][4].
• Child care (inside 624) — the only clean corner of the social half. Because parents pay tuition, the sector's two social-assistance pure-plays sit here: Bright Horizons (BFAM) and KinderCare (KLC) [5].
• The diluted "payviders" — the closest thing to a buy-the-sector vehicle. UnitedHealth's Optum (UNH), Humana's CenterWell (HUM), and CVS Health (CVS) now reach across children — employing tens of thousands of physicians, running outpatient clinics and the largest home-health platforms — but each is buried inside a giant insurer, so you are buying health insurance with a care-delivery overlay, not the overlay by itself [2].

The cross-cutting pattern: listed exposure runs opposite to where the people and the mission are. The most investable corners are the capital-heavy, concentrated, or privately-paid ones (hospitals-as-real-estate, dialysis, labs, senior-living REITs, child care); the vast labor-heavy, government-funded, nonprofit core — most hospital beds, the child-welfare and safety-net system, the disability and behavioral group-home world — is private, nonprofit, or governmental and has no clean public handle. For the full company-by-company map in any child, read that subsector's primer.

5. How the money works

Despite their differences, all four children run on one master identity:

Revenue ≈ volume × net reimbursement per unit — visits, admissions, procedures, tests, bed-days, billable hours, or enrolled children — earned across a payer mix (commercial insurance, Medicare, Medicaid, government grants, private tuition, donations) against a cost base dominated by labor.

Four levers recur across the whole sector:

• Utilization / occupancy is the profit lever. These are labor-heavy businesses with a large fixed base, so the number that matters is how full the schedules, beds, chairs, rooms, and licensed slots are kept. An empty appointment, hospital bed, or day-care seat cannot be inventoried and sold later. Facility count is a weak measure — same-site (organic) volume, payer mix, and cost per unit are what matter in every child.
• Payer mix is destiny. Commercial (employer) insurance and private-pay customers pay a multiple of what Medicaid pays for the same service, so the commercially insured or self-paying minority generates a disproportionate share of profit and cross-subsidizes the government book. Because government payers set or anchor most prices, operators have minimal pricing power — margins live or die on volume and mix, not list price.
• Labor is the product and the largest controllable cost — roughly half of revenue across the sector. The scarce input is a licensed clinician or a low-wage caregiver, and licensure creates local, not national, moats, so barriers to entry are low and competition is local.
• Almost nobody here is priced by a walk-in customer. A government fee schedule, an insurer contract, a state Medicaid rate, a federal grant, or a per-diem sets the price — so revenue quality turns on payer mix and contract terms, not retail demand.

On top of that shared base sit distinct engines worth flagging: fee-for-service billing off Medicare fee schedules (most offices, labs, hospitals); a growing value-based-care / capitation overlay (physician groups and integrated care take a fixed per-member-per-month payment and profit on the spread); occupancy × daily/monthly rate economics (hospitals per-diem or per-case, nursing and senior living per resident-day); private tuition + subsidy (child care, the one child selling to a real paying customer); and grant-and-donation throughput in the safety net (reported "receipts" are not profit; surpluses build reserves, not dividends). Our federal file publishes no sector-wide margin, occupancy, or payer-mix figure, so any such numbers in the child primers come from trade sources and are flagged there as estimates. Do not force regulated-utility rate base, REIT funds-from-operations, or mining cost-per-ounce language onto this sector; its economics are reimbursement-, occupancy-, tuition-, and donation-driven.

6. What drives demand

Demand across sector 62 is largely demographic, clinical, and social — which makes it steadier than the broad economy — with a discretionary overlay only on the cash-pay pieces (elective dentistry, cosmetic and wellness care). The shared drivers:

• Aging population — the universal tailwind. The U.S. population aged 65 and older reached 61.2 million (18.0% of all Americans) in 2024, and all baby boomers will be 65+ by 2030 [7]. Seniors use far more of nearly every service here — more physician visits and surgery, more hospital care, more nursing and senior living, more home care and in-home social services — so rising Medicare enrollment lifts the whole sector.
• Chronic disease and rising medical intensity generate recurring care — repeat labs, imaging, dialysis, chronic-care management, longer survival after serious illness — not one-offs.
• The behavioral-health crisis — high mental-illness and substance-use prevalence, falling stigma, parity law, and telehealth — has pushed demand far past the supply of clinicians and beds, across physician psychiatry, outpatient therapy, psychiatric hospitals, and residential treatment.
• Disability, child-welfare, and safety-net need — long Medicaid waiting lists, food insecurity, homelessness, and disaster caseloads — drive the social half, largely disconnected from the business cycle (and often counter-cyclical while funding is pro-cyclical).
• The site-of-care shift — the master internal story. Better minimally invasive techniques, anesthesia, remote monitoring, and deliberate payer steering keep moving care out of costlier hospitals into outpatient and home settings. This is the biggest reason ambulatory care (621) grows faster than the sector overall — but it is a headwind for hospital inpatient volume (622). It is a reallocation within the sector, not new demand [2][3].

The binding constraint everywhere is workforce. Demand is rarely the problem; staffing is. Strong projected job growth across these professions coexists with chronic shortages of clinicians and low-wage caregivers, which means demand can convert into higher wages rather than higher owner profit — the recurring tension of the whole sector.

7. Regulation

Health care and social assistance is one of the most heavily regulated parts of the economy, and the regulation runs on two axes: a federal payment-and-fraud spine common to almost every child, and profession-by-profession, state-by-state licensure that varies enormously beneath it.

The common federal spine:

• The Centers for Medicare & Medicaid Services (CMS) is simultaneously the biggest customer and the chief regulator. It sets or anchors the prices across most of the sector — physician and lab fee schedules, hospital inpatient and outpatient prospective payment systems, the dialysis bundle, skilled-nursing and home-health rates — usually with no automatic inflation update, so a skinny annual rate notice hits margins directly [2][3][4].
• Fraud-and-abuse law governs money that touches referrals — the Anti-Kickback Statute, the physician self-referral Stark Law, and the False Claims Act — alongside HIPAA (the Health Insurance Portability and Accountability Act) protecting patient data, and EMTALA (the Emergency Medical Treatment and Labor Act) requiring hospitals to screen and stabilize regardless of ability to pay [2][3].
• Corporate Practice of Medicine (CPOM) doctrines in roughly two-thirds of states bar non-clinicians from owning a clinical practice, which is why outside capital enters through a management-services organization (MSO) paired with a clinician-owned professional entity — a fast-rising area of state and antitrust attention [2].

The state-and-profession layer is where the sector fragments: Certificate-of-Need (CON) laws that gate new hospitals, dialysis, and imaging capacity in dozens of states; state licensure of every profession and facility type; the social-side federal money streams that create whole markets (Title IV-E foster care, the Child Care and Development Fund, USDA food programs, HUD housing, FEMA disaster relief, the Rehabilitation Act's vocational grants); and profession-specific rules from DEA telehealth prescribing to FDA biologics licensure [4][5]. The investor takeaway: treat licensure, ownership structure, and payer contracts as transaction-level diligence, not boilerplate — the legal structure varies by profession, facility, and state and is often the difference between a compliant deal and an unwind.

8. Consolidation

By the federal numbers, sector 62 is one of the least-concentrated sectors in the economy — CR4 of 4.4% and HHI of 10.4 [1]. It is, at the national level, a cottage industry of small practices, facilities, agencies, and homes, and that fragmentation is the entire thesis for consolidators, who apply one playbook — professionalize billing, purchasing, staffing, and compliance across many small sites — that has already reshaped dentistry, dermatology, dialysis, and home care. The direction of travel is unmistakably toward consolidation, on several fronts at once:

• Physician and practice roll-ups. By 2024 roughly 78% of U.S. physicians were employed by hospitals, insurers, or corporate/PE-backed entities rather than independent [10]; PE roll-ups are mid-cycle in dentistry, rehab, mental health, disability services, and child care.
• Payvider vertical integration — the apex story. Insurers buying physician groups, surgery centers, and the two largest home-health platforms are integrating payment and delivery under one roof, and are the closest thing to a "buy the sector" force [2].
• REIT and operator M&A in senior living (Welltower alone announced ~$23 billion of transactions in 2025) and hospital and behavioral platform deals [4].

Two things are true sector-wide. Competition is local even when ownership is national — patients get surgery, dialyze, live in a nursing home, and drop children at day care near home — so a firm with a trivial national share can dominate a county, and the "unconcentrated" statistics coexist with real local pricing power. And antitrust scrutiny is rising: a cross-government inquiry by the Federal Trade Commission (FTC), Department of Justice (DOJ), and Department of Health and Human Services (HHS) into corporate and PE ownership of health-care providers; the FTC forcing Sevita to divest 128 facilities before clearing its ResCare acquisition (2026); and the ~164 divestitures the DOJ required in the UnitedHealth–Amedisys home-health merger — all put roll-ups squarely on regulators' radar [9]. A large nonprofit-and-government majority simply is not for sale — most hospital beds, ~80% of retirement communities, food banks, and most disability and youth providers — which caps how far consolidation can run.

9. Key risks

The sector shares a common risk profile, with a different emphasis in each child:

• Reimbursement / Medicaid-policy risk (the dominant risk, sector-wide). Most revenue is a government-set or government-anchored price with little pricing power behind it. The 2025 federal budget-reconciliation law is estimated to cut on the order of $900 billion–$1 trillion of federal Medicaid spending over a decade as it phases in from 2026 — a direct threat across hospitals, nursing homes, home care, and social assistance, hitting rural, Medicaid-dependent, and thin-margin operators hardest [8].
• Labor is the binding constraint (whole sector). Clinician and caregiver scarcity, wage inflation, turnover, and burnout cap both capacity and margin; strong demand can turn into higher pay rather than higher profit [7].
• Commercial / private-pay mix erosion. The profit engine is the commercially insured or self-paying minority; insurer network narrowing, denials, site-neutral payment reform, and Medicare Advantage steering all threaten the cross-subsidy that funds the government-paid book [3].
• Leverage and financial engineering. Debt and sale-leaseback rent make thinly capitalized operators fragile when census dips — the Steward Health Care (hospitals) and Genesis HealthCare (nursing) bankruptcies and the outpatient-rehab leverage bust are live examples [3][4].
• Value-based / capitation execution risk. Full-risk operators eat cost overruns — a surge in senior utilization pushed several capitated providers into bankruptcy in 2023–2024 [2].
• Antitrust and ownership risk. State CPOM rules and rising FTC/DOJ/HHS scrutiny can limit or invalidate PE ownership, MSO control, or roll-up deals in any child [9].
• Quality, litigation, and reputational risk — sharpest where the sector serves the most vulnerable (behavioral, disability, and youth residential care); a single abuse case or safety scandal can end an operator.
• Cybersecurity and measurement risk. System-wide shocks (the Change Healthcare ransomware attack) can freeze cash flow across providers; and the federal statistics exclude nonemployer and much government activity, so a ticker can look like sector exposure while most earnings sit elsewhere. Never read the sector HHI as evidence of a competitive market (Section 3).

10. How to invest, and the outlook

There is no single ticker for NAICS 62, and its headline "unconcentrated" statistics should never anchor a thesis. Invest child by child — and, inside the children, market by market — matching the route to how each business is actually owned. There is no ETF dedicated to the sector.

Public routes — narrow, uneven, and clustered. The cleanest listed exposure sits in a few corners: for-profit hospital chains (HCA, THC, UHS, CYH, Ardent); ambulatory pure-plays in dialysis (DVA, FMS), outpatient surgery (SGRY), and labs (DGX, LH); health-care REITs for residential-care and hospital real estate (WELL, VTR, DOC, OHI, CTRE, MPW); and the two child-care operators (BFAM, KLC). The broadest single-name proxies are the diluted payviders — UnitedHealth/Optum (UNH), Humana/CenterWell (HUM), CVS Health (CVS) — which span physician offices, clinics, and home health but are dominated by their insurance earnings. For every listed name, isolate the actual care-delivery earnings from the surrounding insurance, pharmacy, device, or real-estate businesses before comparing valuation multiples, EBITDA (earnings before interest, taxes, depreciation, and amortization), or dividend yield — and judge it against the medical-cost cycle and government-payment risk, not against facility-count growth.

Private routes — where most of the economics actually sit. Owning sector 62 mostly means owning practices, facilities, agencies, and the real estate under them: direct practice and facility ownership; PE-backed MSO/platform roll-ups across every child; physician-ownership stakes in surgery centers; value-based-care platforms; net-leased medical and group-home real estate; private credit against contracted government cash flows; and — the single largest capital channel into the nonprofit core — tax-exempt municipal / hospital-revenue bonds. In every child, underwrite the local unit economics first — normalized owner cash flow (not headline revenue), same-site collections and occupancy trends, payer contracts and denial rates, staffing and retention, and the ownership-structure terms that make a deal compliant. The large nonprofit and government segments — most hospital systems, most retirement communities, food banks, crisis lines, county and municipal providers — are not investable; the only adjacent security is tax-exempt financing.

Outlook (editorial judgment). The structural demand case across sector 62 is about as durable as any in the economy: an aging, chronically ill population that guarantees rising need for medical, nursing, and in-home care, reinforced by high unmet behavioral demand and sticky safety-net caseloads — against constrained supply of both facilities and workers. But the four children will not move together: ambulatory care, home-based care, senior living, precision diagnostics, and value-based senior care are the clearest growth stories; hospital inpatient volume is a demand-durable but policy-capped grind losing share to outpatient settings; child care is boxed in; and the safety net is funding-whipsawed. This is a low-margin, labor-bound, reimbursement-driven, deeply fragmented sector where reimbursement is the ceiling and margins, not volumes, are the thing to watch — and where winners are decided by unglamorous capabilities (recruiting and keeping staff, negotiating payer economics, running compliant billing and occupancy at scale), not by financial engineering. The single biggest macro swing factor is the federal posture on Medicare and, above all, Medicaid funding. Our ground-truth federal file for NAICS 62 contains no revenue-growth forecast, margin benchmark, or complete ownership census, and none is asserted here. The recurring mistake is treating this two-digit code as one industry, or its "competitive" HHI as real. It is four unlike businesses in one drawer — read the subsector primers (621, 622, 623, 624) before acting on any of them.

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Sources

Section 3 figures for NAICS 62 are our ingested ground-truth federal statistics (stats-62.md), drawn from the U.S. Census Bureau's 2023 County Business Patterns (establishments, employment, payroll) and 2022 Economic Census (firms, receipts, concentration, HHI). Subsector-level figures, tickers, and all external facts are synthesized from the four child primers, which carry the full source lists.

1. U.S. Census Bureau, County Business Patterns 2023 (NAICS 62: establishments 1,003,398; employment 22,063,238; annual payroll $1,394.72B; Q1 payroll $336.13B) and 2022 Economic Census — Concentration of Largest Firms (NAICS 62: receipts $3,330.30B; firms 691,347; CR4 4.4% / CR8 6.7% / CR20 11.7% / CR50 18.9%; HHI 10.4). Histometrics ground-truth extract (stats-62.md). https://www.census.gov/programs-surveys/cbp.html; https://data.census.gov/table/ECNSIZE2022.EC2200SIZECONCEN
2. Histometrics subsector primer, NAICS 621 — Ambulatory Health Care Services (receipts $1,409.92B; CR4 4.1% / HHI 10.3), synthesizing CMS fee-schedule rules, dialysis/lab/surgery operator filings, value-based-care and CPOM sources, and its seven child primers.
3. Histometrics subsector primer, NAICS 622 — Hospitals (receipts ~$1.357T; CR4 8.0% / HHI 34.4; ~80% nonprofit/government beds), synthesizing HCA/Tenet/UHS/CYH filings, MedPAC, CMS payment rules, EMTALA/CON, and its three child primers.
4. Histometrics subsector primer, NAICS 623 — Nursing and Residential Care Facilities (receipts $283.7B; CR4 3.8% / HHI 8.6), synthesizing skilled-nursing, senior-living, and disability/behavioral operator and REIT filings, MedPAC, CMS/HCBS rules, and its four child primers.
5. Histometrics subsector primer, NAICS 624 — Social Assistance (receipts $279.25B; CR4 3.1% / HHI 4.6), synthesizing Bright Horizons/KinderCare/Addus filings, Medicaid HCBS, Title IV-E/CCDF/USDA/HUD/FEMA funding, and its four child primers.
6. Centers for Medicare & Medicaid Services, National Health Expenditure Fact Sheet (2023 data; total NHE ~$4.9T; hospital care ~$1.5T; physician and clinical services ~$978B; nursing-care facilities ~$211B). https://www.cms.gov/data-research/statistics-trends-and-reports/national-health-expenditure-data/nhe-fact-sheet
7. U.S. Census Bureau, Older Adults Outnumber Children in 11 States (65+ population 61.2 million, 18.0% in 2024) and By 2030, All Baby Boomers Will Be Age 65 or Older. https://www.census.gov/newsroom/press-releases/2025/older-adults-outnumber-children.html
8. KFF and related analyses, Medicaid provisions in the 2025 federal budget-reconciliation law (~$900 billion–$1 trillion in federal Medicaid cuts over a decade). https://www.kff.org/medicaid/tracking-the-medicaid-provisions-in-the-2025-budget-bill/
9. U.S. Federal Trade Commission, Department of Justice, and Department of Health and Human Services, Cross-Government Inquiry into Corporate and Private-Equity Ownership of Health Care Providers (2024); FTC, Sevita / ResCare action (2026); DOJ, UnitedHealth–Amedisys divestiture (2025). https://www.ftc.gov/; https://www.justice.gov/opa/pr/justice-department-requires-broad-divestitures-resolve-challenge-unitedhealths-acquisition
10. Physicians Advocacy Institute / Avalere and American Medical Association, physician-employment and practice-arrangement data (~78% of physicians employed by hospitals, insurers, or corporate/PE entities by 2024). https://www.physiciansadvocacyinstitute.org/