Table 1.

Summary statistics

	Age group
	25–34	35–44	45–54
N	643	535	379
Mean year of son's observations	2000	2000	2002
Mean year of father's observations	1977	1975	1976
Mean age of son	28	38	48
Mean age of father	30	40	50
Ranges for birth year of son	1956–1979	1948–1969	1942–1959
Ranges for birth year of father	1937–1961	1927–1950	1917–1938
Mean birth year of son	1971	1961	1953
Mean birth year of father	1946	1934	1925
Mean son's log of labor inc	10.7	10.8	10.8
Mean father's log of labor inc	10.5	10.8	10.9
Std son's log of labor inc	0.72	0.8	0.83
Std father's log of labor inc	0.49	0.56	0.64