Table 1
Summary Statistics of Immigration to Commuting Zones
| 1 | 2 | 3 | 4 | 5 | 6 | |
|---|---|---|---|---|---|---|
| Mean [Standard Deviation] | 1st Percentile | 10th Percentile | Median | 90th Percentile | 99th Percentile | |
| Percent immigrants in CZ population, 1990 | 2.75 [3.8] | 0.212 | 0.547 | 1.4 | 5.73 | 22.1 |
| Percent low-education immigrants in CZ population, 1990 | 1.92 [3] | 0.107 | 0.302 | 0.88 | 4.71 | 18.6 |
| Percent low-education in CZ’s immigrant population, 1990 | 64 [13.9] | 31.1 | 47.7 | 63 | 84 | 94.1 |
| Percent change from 1980 to 1990 in CZ’s low-education immigrants | −9.64 [52.3] | −74.7 | −56.6 | −23.6 | 60.8 | 199 |
| CZ sample size in 1970 | 11,852 [14,942] | 4,943 | 5,593 | 9,039 | 16,823 | 65,530 |
| CZ sample size in 1980 | 20,222 [40,162] | 5,022 | 5,661 | 10,917 | 32,730 | 175,222 |
| CZ sample size in 1990 | 22,324 [40,898] | 5,244 | 6,779 | 12,998 | 36,298 | 194,109 |
Notes: Data from 1980 and 1990 U.S. Census (IPUMS: Ruggles et al. 2010). CZ means commuting zone, a group of counties that make up an integrated local labor market. Summary statistics describe the distribution across the 741 CZs in the United States. Immigrants are those born outside U.S. states or territories. Low-education means high school or less. Population counts reflect population weights and include children (young children all have low education). Census samples do not always identify CZ. Estimate of CZ c sample size is
(where p indexes PUMAs and wpc is the share of CZ c population that is in PUMA p. See Appendix 3 for derivation.
