Table 1.

Effects of bracero exclusion on real wages: Differences-in-differences with continuous treatment, quarterly

	Wage, all years		Wage, 1960–1970
Dep. var.	Hourly composite	Daily w/o board	Hourly composite	Daily w/o board
$I_{t\ge 1965}·{\overline{\ell }}_s^{1955}$	−0.0356	−0.385	−0.0401	−0.0247
	(0.0426)	(0.495)	(0.0315)	(0.309)
N	4324	5813	2024	1901
adj. R2	0.773	0.835	0.733	0.758
Clusters	46	46	46	46
Semielasticity $\frac{\partial lnw}{\partial (B/L)}$	−0.0831	−0.110	−0.0750	−0.0410
	(0.0654)	(0.0916)	(0.0507)	(0.0541)
p-val. χ2 test: $\frac{\partial lnw}{\partial (B/L)}=0.1$	[0.0075]	[0.0263]	[0.0012]	[0.0124]

‘Treatment’ is the degree of exposure to exclusion. Observations are state-quarters. All regressions include state and quarter-by-year fixed effects. Standard errors clustered by state in parentheses. ℓ̄₁₉₅₅ is average fraction of Mexicans among the state’s total hired seasonal workers across the months of 1955. Wages in constant 1965 US$ deflated by CPI. Hourly wage has full state coverage but fewer years (1948–1971); daily wage has more years (1942–1975) but is missing for three states (CA, OR, WA) in most quarters after 1949Q1. Farm worker stocks missing in original sources for 1955 in Rhode Island and New Hampshire. Semielasticity is the coefficient on $I_{t\ge 1965}·{\overline{\ell }}_s^{1955}$ in an otherwise identical regression with ln wage as the dependent variable.