Taxation and Entrepreneurship in the United States

Layer 1: Overview

This paper investigates how the level and progressivity of personal income taxes shape entrepreneurial activity in the United States, contributing empirical evidence, theoretical intuition, and a structural quantitative evaluation. The motivation is both descriptive — entrepreneurs own more than 40% of total capital and hire more than half of private-sector workers, yet their share of the population varies substantially across states and time — and normative, given growing policy interest in more redistributive taxation. The central question is whether a more progressive tax system, which simultaneously reduces the risk and the return to entrepreneurship, produces more or fewer entrepreneurs in practice.

The empirical analysis draws on CPS microdata from 1962 to 2019 (entrepreneurs defined as households where the head or spouse is self-employed, averaging 11.7% of the national population), County Business Pattern data from 1986 to 2018, Business Dynamics Statistics, and NBER TAXSIM. Tax measures — both average tax rates at the 50th, 90th, and 95th percentiles of the national earnings distribution and a parametric Benabou (2002) tax function with a level parameter theta_0 and a progressivity parameter theta_1 — are constructed by applying TAXSIM to a fixed 2010 CPS cross-section across all 51 state-year cells from 1977 to 2019, thereby limiting endogeneity from tax-code-induced changes in the observed income distribution. The benchmark panel regression includes state and year fixed effects, state-level economic and demographic controls, lagged local business cycle variables, and local non-linear time trends; the benchmark outcome is measured two years after the tax change. Instrumental variables — lagged state tax rates plus contemporaneous federal rates — are used to further address endogeneity.

The core empirical findings are strongly negative across all measures of entrepreneurship and all tax measures. A one-percentage-point increase in the average tax rate at median income reduces the number of entrepreneurs by 4.5% (coefficient -0.0449, significant at 1%); a one-standard-deviation increase in that tax rate (about 2.35 percentage points) implies roughly 9.7% fewer entrepreneurs. Negative effects also hold for college-educated entrepreneurs and for firm-side proxies (number of small establishments, employment at small establishments). For tax progressivity, holding tax level constant, a one-percentage-point increase in the average tax rate at twice average earnings reduces the number of entrepreneurs by about 15%. Using the parametric progressivity measure, an increase in theta_1 of 0.01 (about 60% of the cross-state standard deviation) reduces the total number of entrepreneurs by approximately 10% and the number of small establishments by about 2.5%. These results hold under additional lagged controls, different horizons (negative and significant through about nine years for the count of entrepreneurs, more persistent for firm-side measures), and IV estimation (IV magnitudes are one to three times larger than OLS, with first-stage F-statistics of 136 and 112 for the progressivity instrument). A subsample analysis around major federal tax reform years (1988, 1991–1993, 2001) finds consistent signs but smaller and noisier estimates given the reduced sample size.

To explain these patterns, the paper develops a life-cycle overlapping-generations incomplete-markets model in the spirit of Quadrini (2000) and Cagetti and De Nardi (2006). Households are heterogeneous in age, innate ability, idiosyncratic labor and entrepreneurial productivity shocks, risk aversion (distributed uniformly over three values), and asset holdings. Entrepreneurs face a collateral constraint (capital bounded by theta times assets), a fixed operating cost each period, and a switching cost when exiting to wage employment. The same progressive tax function applies to both workers and entrepreneurs. The model is calibrated to U.S. data: exogenous parameters include an inverse Frisch elasticity of 1, labor productivity persistence of 0.929 and standard deviation of 0.227 (from Chang and Kim 2007), a 45-year working life, and returns to scale in entrepreneurship of 0.85. Eight parameters — including the discount factor, entrepreneurial productivity persistence and dispersion, operating cost, switching cost, and risk-aversion dispersion — are estimated via simulated method of moments, matching 21 moments including the entrepreneur population share, income and wealth shares of entrepreneurs, fraction of entrepreneurs with negative profits, and aggregate wealth distribution. The model matches the data well on targeted and untargeted moments.

The main structural counterfactual holds average tax rates constant and varies progressivity. Converting to a flat tax (theta_1 = 0) increases the number of entrepreneurs by about 15% in general equilibrium. Aggregate output rises by about 11% and the capital stock falls by about 27% when progressivity doubles from 0.13 to 0.26 (relative to the benchmark of theta_1 = 0.13). The return effect — more progressive taxes compress the expected return to entrepreneurship relative to wage work — quantitatively dominates the insurance effect (more progressive taxes reduce the variance of entrepreneurial income). The distributional analysis shows that medium-productivity entrepreneurs are more sensitive to tax changes than high-productivity ones; older, wealthier entrepreneurs are also more responsive. For welfare, the socially optimal progressivity level — measured by ex-ante expected lifetime welfare of unborn agents in steady state — is theta_1 = 0.109, only about 16% less progressive than the current U.S. benchmark of 0.13. The welfare gains from this reform are described as tiny. The welfare-optimal policy reflects the trade-off between efficiency losses (from reduced entrepreneurship and output) and distributional gains (from redistribution to below-average-income households, who benefit from more progressive taxation). Raising the average tax level while holding progressivity constant also reduces output and capital, with capital falling by roughly 40% and output by about 10% when the level parameter doubles; these effects interact with progressivity in non-linear ways captured only through the structural model.

Layer 2: Deep Dive

What is the identification strategy in the empirical analysis and what are the main threats to it?

The benchmark strategy is a state-year panel regression with state and year fixed effects, state-level economic and demographic controls (real GDP per capita, sector employment shares), and lagged local GDP growth rates and unemployment rates over four years before the tax measure. The dependent variable is measured two years after the tax change to allow recognition lags. IV instruments are constructed as the sum of the lagged (by two years) state tax rate at the relevant income percentile and the current federal marginal tax rate at that percentile, following Akcigit et al. (2018); for progressivity, lagged theta_1 and theta_0 are used as instruments, with first-stage F-statistics of 136 and 112 respectively, ruling out weak instruments. A further alternative IV constructs hypothetical tax parameters by applying current federal rates to state-level rates lagged by two years via TAXSIM. Main threats are (1) endogeneity of state tax policy to local economic conditions — addressed through the rich set of lagged business cycle controls, state-specific quadratic trends, and IV; (2) income-composition endogeneity in estimating the tax function — addressed by fixing the CPS 2010 sample and scaling incomes by average wage growth rather than using the contemporaneous distribution; (3) short sample periods around major reform years, which make the reform-event analysis underpowered.

What are the main mechanisms through which taxes affect entrepreneurial choice, and how are they distinguished?

The paper identifies two opposing forces from greater tax progressivity. The return effect: higher progressivity reduces the average after-tax payoff to entrepreneurship, because entrepreneurs earn above-average incomes and the progressive schedule compresses post-tax profits relative to wages. The insurance effect: higher progressivity also reduces the variance of after-tax entrepreneurial income, making entrepreneurship less risky and potentially more attractive to risk-averse agents. The simple theoretical models (mean-variance utility with lognormal profits and CRRA utility) show that the sign of the net effect is theoretically ambiguous. In the quantitative model — and in the data — the return effect dominates: flatter taxes raise entrepreneurial entry. The two effects are separated analytically in the simple model (Section 4) and quantitatively in the structural model by examining partial-equilibrium versus general-equilibrium effects and by isolating the capital demand response (sensitive to progressivity) from the labor demand response (less sensitive).

What heterogeneity across entrepreneurs and along the life cycle is documented?

Empirically, the negative tax effect is larger for college-educated entrepreneurs than for non-college entrepreneurs when measured by high-income tax rates (90th and 95th percentiles), consistent with higher-educated entrepreneurs having higher incomes. In the structural model, medium-productivity entrepreneurs lose the most when progressivity rises: when theta_1 doubles, the medium-productivity group’s share falls by 0.84 percentage points from a base of 9.08%, while the high-productivity group falls by only 0.11 points from 3.47%. Older and wealthier households are more sensitive to progressivity changes because the return effect matters more relative to the insurance effect for those who have accumulated wealth. Risk aversion heterogeneity (modeled as uniform dispersion around 2.5) affects saving and occupational choice; more risk-averse households are more sensitive to the variance reduction from progressive taxes, but the model shows this does not reverse the dominance of the return effect in aggregate.

What robustness checks are run?

The robustness battery includes: (1) adding state-specific quadratic time trends and longer lags of local business cycle variables; (2) two IV strategies — lagged state tax rates plus current federal rates, and hypothetical tax measures constructed from TAXSIM with lagged state and current federal components; (3) controlling for lagged entrepreneurial activity levels (log number of entrepreneurs and establishments lagged two years); (4) examining effects at horizons from t+0 to t+10 via local projection methods, finding effects most pronounced in the short run and diminishing over about nine years for entrepreneur counts but more persistent for establishment and employment measures; (5) restricting the sample to years around major federal tax reforms (1988, 1991–1993, 2001) and finding consistent negative signs even though magnitudes are weaker given the smaller sample; (6) using alternative measures of progressivity (differences between tax rates at multiples of average earnings) as a robustness check on the parametric theta_1 measure; (7) structural model sensitivity analysis varying each estimated parameter individually to confirm monotonic identification of moments.

How does this paper relate to and differ from prior empirical and structural work?

Empirically, it extends Gentry and Hubbard (2000), who used PSID data 1978–1993 to document that progressive marginal rates discourage self-employment, and Cullen and Gordon (2007), who used IRS cross-sectional data to study the role of tax incentives in business formation. The current paper uses a much larger micro-level dataset (CPS, CBP, BDS), covers both cross-sectional and time-series variation across all U.S. states from 1962 to 2019, examines a broader set of entrepreneurial outcomes (count, employment, establishment dynamics), and controls rigorously for local trends and business cycles. Structurally, it is in the tradition of Quadrini (2000), Cagetti and De Nardi (2006), and Kitao (2008), but uniquely combines a life-cycle OLG framework with empirically estimated tax progressivity and a novel SMM estimation of key entrepreneurial parameters including risk-aversion dispersion. Unlike Meh (2005), which studies switching from progressive to proportional tax in a similar model, this paper brings empirical discipline via state-level identification and explicitly estimates the optimal progressivity. Unlike Brüggemann (2017), which focuses on optimal top marginal rates, this paper studies the full distribution and links it to state-level quasi-experimental evidence. Scheuer (2014) studies optimal taxation with endogenous entry theoretically; this paper complements that with quantitative general-equilibrium analysis.

What are the policy implications and their scope conditions?

The main policy implication is that tax progressivity has a quantitatively large negative effect on entrepreneurship and output: converting to a flat tax (holding average tax revenue constant) would increase the number of entrepreneurs by about 15% and GDP by about 11%. However, the welfare-optimal progressivity is only marginally less than the current U.S. level (optimal theta_1 of 0.109 versus benchmark of 0.13, about 16% less progressive), implying the welfare gains from flattening taxes are tiny. This is because redistribution from high-income entrepreneurs to below-average-income workers and retirees is welfare-improving even as it reduces aggregate output. The results hold in both general equilibrium (where wages and interest rates adjust) and in partial equilibrium (more relevant for state-level comparisons, where PE effects are somewhat stronger). The scope conditions include: the model abstracts from age-dependent taxation, occupational-specific tax treatment, endogenous human capital accumulation by entrepreneurs, wealth taxes, and the distinction between corporate and pass-through taxation. These omitted features could alter the optimal progressivity result.

What do the general equilibrium versus partial equilibrium comparisons reveal?

Partial equilibrium effects (constant wages and interest rates, approximating the small open economy view of U.S. states) are somewhat stronger than general equilibrium effects. This is consistent with the empirical panel estimates, which more closely correspond to PE since state economies face roughly fixed factor prices from the national market. When progressivity doubles in PE (adjusting average tax), the entrepreneur share falls more than in GE, and the optimal progressivity in PE is higher than in GE because in GE there is an additional channel: lower capital stock from reduced entrepreneurship depresses wages, imposing an additional cost on workers that is absent in PE. This comparison validates using PE as the interpretive benchmark for the empirical regressions.

What does the model say about the interaction between tax level and tax progressivity?

The model reveals a non-linear interaction that cannot be separated in empirical analysis. When tax progressivity is held at zero (flat tax), the entrepreneur share declines smoothly as the tax level rises. At benchmark progressivity, the entrepreneur share exhibits a non-monotonic relationship with the level: for very low tax levels the share is high, it falls as taxes rise, but at sufficiently high levels the entrepreneur share may rise again because workers’ wealth effects lead to higher labor supply, partially offsetting the dampening of entrepreneurial returns. At doubled progressivity, the non-monotonicity is more pronounced. Tax revenue also exhibits a Laffer-curve pattern with respect to the level parameter across all progressivity scenarios, though this is not the paper’s primary focus.

What quantitative moments does the calibrated model match, and where does it fall short?

The model matches an aggregate capital-to-output ratio of 2.716 (data: 2.650), entrepreneur population share of 12.6% (data: 12.1%), employment hired by entrepreneurs of 55.9% (data: 56.0%), share of entrepreneurs with negative profits of 12.2% (data: 11.0%), average exit rate of 9.4% (data: 17.0%, a notable miss), average age of entrepreneurs of 44.4 (data: 49.2, another miss), entrepreneur income and wealth shares across the distribution, and top household wealth shares. The model overshoots capital and wealth shares for the top decile relative to data but matches the middle of the distribution well. The average age and exit rate mismatches are acknowledged; the operating-cost and switching-cost parameters are the primary levers for these, and the paper notes that exit costs (rather than entry costs) are more effective at generating entrepreneurs with negative profits.

Key Concepts

Tax progressivity (theta_1): The progressivity parameter in the Benabou (2002) tax function ya/AE = theta_0*(y/AE)^(1-theta_1): a higher theta_1 means after-tax income rises less than proportionally with pre-tax income, implying marginal rates increase with income. In the paper’s measure, theta_1 = 0 is a flat tax and the U.S. benchmark is estimated at 0.13. Progressivity is measured separately from the average tax level (controlled by theta_0), allowing the two to vary independently in both empirics and counterfactuals.

Return effect vs. insurance effect: The two opposing forces through which tax progressivity affects entrepreneurial choice. The return effect is the compression of average after-tax entrepreneurial profits relative to wages — since entrepreneurs earn above-average incomes, progressive taxes reduce the relative net payoff to entrepreneurship. The insurance effect is the reduction in after-tax income variance for entrepreneurs — progressive taxes act as partial insurance against bad profit realizations. The paper finds the return effect quantitatively dominates in both the simple theoretical models and the calibrated quantitative model.

Collateral constraint: The restriction k <= Theta*a in the model, where k is the entrepreneur’s capital input and a is her asset holdings. This models credit market frictions: an entrepreneur can borrow and invest no more than Theta - 1 times her own wealth in the business. Set to Theta = 0.35 in calibration (following Midrigan and Xu 2014), this constraint links entrepreneurial capital demand to wealth accumulation, making the tax-wealth-capital nexus a central quantitative mechanism.

Entrepreneur switching cost (Gamma_s): A cost paid by an entrepreneur who exits to wage employment in the current period. In the calibrated model, Gamma_s = 1.005 (in units of average earnings). This switching cost generates inertia in occupational choice: entrepreneurs with temporarily low productivity may remain rather than exit, generating the empirical share of entrepreneurs with zero or negative profits. It also contributes to life-cycle patterns of entrepreneurship by raising the bar for exit among older, wealthier incumbents.

Ex-ante welfare measure: The paper’s social welfare criterion: the expected lifetime utility of an unborn agent at the beginning of life (age 1), averaging over all initial states (innate ability, initial labor and entrepreneurial productivity draws), and taking the maximum of the worker and entrepreneur value functions. This differs from ex-post welfare (which conditions on realized occupational choice) and is the basis for the optimal tax progressivity calculation. The welfare-maximizing theta_1 = 0.109 uses this criterion.

Progressivity wedge (PW): A summary statistic for tax progressivity defined as PW(y1, y2) = 1 - (1 - T’(y2))/(1 - T’(y1)) for pre-tax incomes y1 < y2. Under the Benabou tax function, the wedge is uniquely determined by theta_1 and equals zero for a flat tax, approaching 1 as the marginal tax rate at the higher income approaches 100%. This measure allows comparison of progressivity across tax systems independently of the level of tax rates.

Simulated method of moments (SMM): The estimation procedure used for eight model parameters (discount factor beta, entrepreneurial productivity persistence rho_z and dispersion sigma_z, operating cost Gamma_f, switching cost Gamma_s, labor disutility chi, aggregate productivity A, and risk-aversion dispersion sigma_U). The procedure minimizes the weighted distance between 21 model-implied moments and their data counterparts, with a diagonal weighting matrix that puts larger weights on the aggregate capital-to-output ratio and the overall entrepreneur population share.