Health Sector Structural Change

Layer 1: Overview

The paper investigates why the U.S. health-services sector has simultaneously experienced a tripling of relative prices since 1948 and a rise in the personal consumption expenditure (PCE) share from under 5% in the late 1940s to 19.6% by 2022. The authors attribute this structural transformation to three candidate drivers: (1) rising relative health-sector markups, (2) unbalanced technological change (differential TFP growth rates across sectors), and (3) changes to the composition of demand from population aging and improving health-investment efficiency.

The paper proceeds in two stages. First, a growth-accounting decomposition uses a two-sector Dixit-Stiglitz monopolistically competitive model to identify growth rates of relative markups and health-sector TFP directly from sectoral input/output data (NIPA PCE, BEA Fixed Asset Tables, Penn World Tables). The non-health capital intensity is set at 0.40 (from Horenstein and Santos 2019) and health-sector capital intensity at 0.26 (from Donahoe 2000). Because health is more labor-intensive than non-health (alpha_h < alpha_c), GE effects on input prices actually dampen relative price growth. In the baseline decomposition (1954-2019), average annual relative markup growth is estimated at 1.6%, with cumulative growth of approximately 186%. When allowing for a time-varying non-health labor share, relative markup growth rises to 2.0% annually and 255% cumulatively. Average annual health-sector TFP growth is 0.3% (baseline) and 0.2% (time-varying labor share), compared to 0.7% for the non-health sector per Penn World Tables. If no markup growth is assumed, the implied health-sector TFP growth falls to -1.3% annually, implying a 56.3% cumulative decline from 1954 to 2019, which the authors regard as implausible in light of observed healthcare advances. Across all four decomposition exercises, GE effects consistently dampen rather than amplify relative price growth, indicating that demand-side composition shifts from aging play at most a minor role in driving prices.

Second, the paper builds and calibrates a full general-equilibrium overlapping-generations model (calibration period 1960-2015, in 5-year intervals) with endogenous survival probabilities following Hall and Jones (2007), monopolistic competition, and a PAYG social security system. The model is calibrated to match five time series: relative health price, life expectancy, health expenditure share, capital share in health production, and labor share in health production. The baseline GE model additionally fits the non-targeted decline in average GDP growth rates well. In the baseline calibration, health-sector TFP is estimated to have grown at 0.3% annually from 1950-1970, accelerating to 0.8% (1975-1980), 1.3% (1985-1995), and 1.5% thereafter — faster than the non-health sector’s 0.7% after the mid-1970s. These GE-corrected estimates exceed those from partial-equilibrium exercises because the growth-accounting approach fails to account for factor-input endogeneity; the true GE path requires health-sector TFP to outpace non-health TFP to reconcile observed relative price growth with the magnitude of markup increases.

Counterfactual simulations isolate each channel. When only demand effects operate (population growth and health-investment efficiency improvements), relative prices rise by only 6.4% compared to 131% in the predicted baseline, and the health share of expenditure rises by 0.004 percentage points versus 0.171 in the baseline — confirming the minor role of aging and demand-composition change. Rising markups alone reproduce nearly all relative price growth but drive expenditure shares up via price rather than quantity increases. Unbalanced TFP growth (with health-sector TFP growing faster post-1975) contributes to real output expansion in the health sector, partially drives up the expenditure share through quantities, supports GDP growth, and — by raising the real value of health services — sustains life-expectancy gains. By 2050, the baseline calibration projects health-sector markups to be approximately 6 times non-health-sector markups if the estimated 1.7% average annual markup growth continues.

The policy implication is direct: market concentration — documented by HHI levels exceeding 2,500 in the majority of U.S. metropolitan areas, with 19% of MSAs having a single monopolistic hospital provider in 2017 — is the primary driver of rising relative health prices. Antitrust enforcement and policies encouraging technology adoption would together address price growth without sacrificing the real productivity gains that have driven longevity improvements. However, welfare analysis of such policies requires distinguishing between curbing care-provider market power versus pharmaceutical/equipment-manufacturer market power, the latter involving R&D investment incentives that the current aggregate model cannot disentangle.

Layer 2: Deep Dive

What is the identification strategy for relative markup growth, and what are the main threats to it?

Relative markup growth is identified from the growth-accounting expression derived from a two-sector Dixit-Stiglitz model: the growth rate of the health-services share of aggregate consumption can be decomposed into relative markup growth, non-health TFP growth (from Penn World Tables), growth in sectoral capital and labor inputs (from BEA and NIPA), and aggregate consumption growth. Taking the capital intensity of the non-health sector as given (alpha_c = 0.40 from Horenstein and Santos 2019) and the data series as known, relative markup growth is backed out residually without requiring knowledge of health-sector TFP or alpha_h. Key threats: (1) the assumption that wages are equalized across sectors (the paper documents supporting evidence in Supplemental Appendix B.6); (2) the constancy of alpha_c, though a time-varying labor-share extension relaxes this; (3) the Dixit-Stiglitz framework abstracts from market selection and endogenous concentration, so markups are characterized as symmetric representative-firm markups rather than firm-distribution markups; (4) the Horenstein and Santos (2019) alternative markups from Compustat cover only publicly traded firms and may understate aggregate markup growth before the 1980s corporatization wave, biasing downward their markup-growth estimates and biasing upward implied TFP-growth estimates for that period.

What are the main mechanisms and how are they distinguished empirically?

The three mechanisms are: (1) rising relative markups (supply-side pricing power), (2) unbalanced TFP growth (sector-differential productivity), and (3) changing demand composition (aging and health-investment efficiency). In the partial-equilibrium growth-accounting stage, the three are separated algebraically in equation (8): relative price growth equals relative markup growth plus a GE-effect term (which captures input-price ratio variation and thus embeds demand composition effects) plus relative TFP variation. In the full GE counterfactual stage, channels are separated by switching them off one at a time (fixing gN = gz = gζj = 0 for demand; fixing µt at its 1955 level for markups; fixing gAc = gAh = 0 for TFP), and by activating only one channel at a time. Table 3 presents the counterfactual outcomes for five targeted moments (relative price growth, life-expectancy change, health expenditure share change, capital and labor input shares) under each scenario.

What does the paper find about health-sector TFP growth, and how does this revise the literature?

The standard view (Triplett and Bosworth 2004; Bates and Santerre 2013) treats health as a ‘cost-disease’ sector with near-zero or negative TFP growth. The paper challenges this: in the baseline partial-equilibrium decomposition, health-sector TFP grows at 0.3% per year on average (1954-2019), compared to -1.3% per year in a model that ignores markup growth entirely. In the full GE model, health-sector TFP growth is higher still — 0.3% (1950-1970), 0.8% (1975-1980), 1.3% (1985-1995), and 1.5% thereafter — eventually exceeding the non-health sector’s 0.7% annual rate. The authors argue this upward revision is correct: partial-equilibrium exercises omit GE feedback effects through factor-input reallocation, and prior studies that did not account for rising markups mechanically attributed all relative price growth to slow TFP growth, biasing health-sector TFP estimates downward.

What role does population aging and demand-composition change play, and what is the channel?

Demand composition changes (population aging and improvements in health-investment efficiency ztζjt) have only a minor role. In GE, such changes can affect input prices (r/w) and thereby health prices only if the health sector uses a different capital intensity than the non-health sector (alpha_h ≠ alpha_c); the elasticity of relative price with respect to the input-price ratio is (alpha_h - alpha_c), which is negative since health is more labor-intensive. This means demand effects actually dampen rather than amplify relative price growth. In the counterfactual where only demand effects operate, relative prices rise by only 6.4% (versus 131% in the predicted baseline from 1960-2015), and the health expenditure share increases by only 0.004 percentage points (versus 0.171 in the predicted baseline). Demand effects do, however, significantly affect life expectancy: shutting them off while allowing only markups produces declining life expectancy, illustrating that income growth and health-investment efficiency improvements are central to longevity gains.

What heterogeneity is documented?

The model features age heterogeneity in three dimensions: (1) age-specific health elasticity θj (how much health expenditure converts to health status); (2) age-specific health output intensity φj; (3) age-specific health-investment productivity ζjt, borrowed from Hall and Jones (2007). These parameters allow older individuals to have lower elasticities of health status with respect to health expenditure, matching the empirical regularity that older patients benefit less per dollar spent on health care. The paper also documents heterogeneity in the sub-components of the health PCE aggregate: over time, prescription drugs and medical appliances have declined in their relative contribution to aggregate health price increases, while hospital services have increased in their relative contribution, consistent with Cooper et al. (2019) on hospital pricing power. Across calibrations, health-sector TFP growth rates vary across four eras, reflecting the different pace of productivity improvements over time.

What robustness checks are run?

The authors conduct four different decomposition exercises in the partial-equilibrium stage: (a) baseline with constant non-health capital intensity; (b) time-varying non-health labor share; (c) using Horenstein and Santos (2019) markups from Compustat for publicly traded firms; (d) zero relative markup growth as an extreme baseline. In Supplemental Appendix C.2 they also invert the identification: they set health-sector TFP growth to values from the literature (-0.6% to 0.4% per year) and back out alpha_h, obtaining values between 0.25 and 0.38, consistent with the externally calibrated 0.26. Five full GE calibrations correspond to the five decomposition assumptions. Model fitness is assessed via RMSE across the five targeted moments; the baseline calibration fits best. An untargeted validity check against observed average GDP growth rates over 5-year intervals further supports the baseline model. Results from alternative calibrations’ counterfactuals are presented in Supplemental Appendix D.6.

How does this paper relate to and differ from closely related prior work?

The closest antecedents are: (1) Horenstein and Santos (2019), who attribute rising U.S. relative health prices to markups and price wedges using Compustat data; the present paper both uses their results and critiques them for under-coverage of non-publicly-traded firms. (2) Hall and Jones (2007), who model health investment, endogenous survival, and the demand side; the present paper embeds their survival technology into a two-sector GE model and adds the supply-side markup and TFP structure. (3) Fonseca et al. (2021, 2023), who account for the rise in health expenditure and cross-country health price differences; the present paper complements them by jointly modeling prices and quantities in a structural change framework. (4) Zhao (2014), who asks why health expenditure shares have risen from a demand side; this paper explores the supply-side (markup and TFP) counterpart. (5) Cost-disease literature (Baumol 1967; Triplett and Bosworth 2004): the paper directly challenges the ‘cost disease’ narrative by showing health-sector TFP is positive and — once GE and markup effects are controlled for — possibly faster than the rest of the economy. Distinctive contributions include the joint treatment of relative prices and real output quantities in structural change, the full GE calibration with endogenous population aging, and the explicit separation of health-care-quantity TFP from health-investment efficiency (the ztζjt composite).

What are the policy implications and their scope conditions?

The primary policy implication is that antitrust enforcement targeting market concentration in health services is the most direct lever for reducing relative price growth, since markup growth is almost entirely responsible for rising relative prices. A secondary policy recommendation is to encourage technology adoption in the health sector to sustain the high TFP growth that has benefited consumers through output expansion and life-expectancy improvements. The authors caution, however, that the model uses a broad definition of the health-services sector (encompassing care providers, pharmaceutical companies, and equipment manufacturers), and welfare implications differ sharply depending on whether policies target care-provider pricing power versus pharmaceutical/equipment pricing power, the latter involving R&D investment incentives. The model cannot disaggregate the sources of health-sector productivity growth, so the precise antitrust strategy requires further research. Additionally, the paper abstracts from 2020 short-term fluctuations and focuses on long-run structural change, so findings are most relevant for secular policy rather than cyclical interventions.

What is the role of unbalanced TFP growth for GDP and life expectancy?

Counterfactual simulations reveal that unbalanced TFP growth — which in the baseline calibration favors the health sector after the mid-1970s — supports aggregate GDP growth. In the counterfactual where TFP growth is turned off (both sectors), GDP grows more slowly because the main remaining driver of income growth is exogenous population growth. The panel (f) of Figure 7 shows that GDP growth is slower without unbalanced TFP variation. For life expectancy, the absence of TFP growth causes life expectancy to rise until the 1980s then stagnate (purple line, panel (b) of Figure 7), since rising income is needed to purchase longevity gains through health investment. The interaction between income growth from TFP and the endogenous demand for health investment is central: health services function as a luxury good in the model, so income growth drives up the quantity demanded and thus survival rates.

What does the paper find about the current level and trajectory of relative markups?

In the baseline calibration, health-sector markups were approximately 1.18 times non-health-sector markups in 1955. By 2010, this ratio had risen to approximately 3.2. The time-varying labor-share model implies even faster growth, from 1.09 in 1955 to 3.9 by 2010. Horenstein and Santos (2019) markups (slowest) go from 1.10 in 1955 to 3.04 in 2010, still a 176% increase. Under the baseline calibration projecting continued markup growth at 1.7% annually, health-sector markups would reach approximately 6 times non-health-sector markups by 2050. These projections are corroborated by micro evidence: HHI for managed care exceeds 2,500 in all California counties (Tawil and DiGiorgio 2022); national MSA-level hospital-bed HHI rose from 5,426 in 2007 to 5,808 in 2017; and 19% of MSAs had a single monopolistic provider in 2017 (Johnson and Frakt 2020).

Key Concepts

Relative markup: The ratio of the health-sector markup (price over marginal cost in a Dixit-Stiglitz monopolistically competitive equilibrium) to the non-health-sector markup; variation in this ratio is identified from sectoral input/output data and is almost entirely responsible for rising relative health-services prices.

Unbalanced technical change: Differential rates of TFP growth across the health and non-health sectors; in models with homothetic preferences and identical factor intensities, relative prices move inversely with relative TFP, but in the paper’s GE setting with different capital intensities the relationship is modified by GE input-price effects.

Health-investment efficiency (ztζjt^θj): An age-specific and time-varying composite productivity term governing how effectively a dollar of health-services expenditure (hjt) converts into improved health status and survival probabilities; it captures environmental, behavioral, and knowledge-based factors orthogonal to health-sector TFP (Aht), and is borrowed from Hall and Jones (2007).

GE (general equilibrium) effect: In the price-decomposition framework, the term (αh − αc)(gLh,t − gKh,t) capturing how changes in the economy-wide capital-labor ratio — driven by demographic change, markup growth, and TFP changes — feed back into relative sector input prices and thereby into relative health prices; because αh < αc, this effect consistently dampens relative health-price growth.

Cost disease: The Baumol (1967) hypothesis that labor-intensive sectors like health services experience slow TFP growth, causing their relative prices to rise as economy-wide wages grow; the paper challenges this characterization by showing health-sector TFP growth is positive and, once GE and markup effects are controlled for, exceeds that of the non-health sector after the mid-1970s.

Corporatization of health services: The historical transition of health-services providers from not-for-profit and public-sector organizations to for-profit investor-owned corporations (including private equity-backed systems), which the paper argues has driven the increase in aggregate health-sector markups and whose timing explains why Compustat-based markup estimates from the 1970s understate long-run markup growth.

Endogenous population / survival rate: In the model, survival probabilities are functions of individual health-services expenditure (hjt) and health-investment efficiency; this makes population aging partly endogenous to health-sector pricing and productivity, linking structural change in health to aggregate life-expectancy dynamics and GDP growth within a unified OLG framework.