Table 4
Workers by Means of Transportation to Work – 1980 - 2000
1980 - 2000 Decennial Censuses
County		Drive					Work	Total
of Residence		Alone	Carpool	Transit	Walk	Other	at Home	Workers
	1980	311,329	80,722	63,326	24,059	17,247	8,767	505,450
	% of Tot	61.6%	16.0%	12.5%	4.8%	3.4%	1.7%	100.0%
	1990	422,775	80,773	63,138	25,136	16,483	24,886	633,191
Alameda	% of Tot	66.8%	12.8%	10.0%	4.0%	2.6%	3.9%	100.0%
	2000	450,496	93,652	72,174	21,919	16,728	23,941	678,910
	% of Tot	66.4%	13.8%	10.6%	3.2%	2.5%	3.5%	100.0%
	1980	199,707	53,165	25,794	6,851	7,603	5,634	298,754
	% of Tot	66.8%	17.8%	8.6%	2.3%	2.5%	1.9%	100.0%
Contra	1990	286,754	55,488	31,344	7,371	6,563	13,653	401,173
Costa	% of Tot	71.5%	13.8%	7.8%	1.8%	1.6%	3.4%	100.0%
	2000	310,286	59,769	39,652	6,631	6,694	18,976	442,008
	% of Tot	70.2%	13.5%	9.0%	1.5%	1.5%	4.3%	100.0%
	1980	69,783	19,349	13,500	4,220	5,022	3,814	115,688
	% of Tot	60.3%	16.7%	11.7%	3.6%	4.3%	3.3%	100.0%
	1990	82,714	15,535	12,899	3,739	2,031	8,162	125,080
Marin	% of Tot	66.1%	12.4%	10.3%	3.0%	1.6%	6.5%	100.0%
	2000	82,898	13,597	12,797	3,835	2,392	11,127	126,646
	% of Tot	65.5%	10.7%	10.1%	3.0%	1.9%	8.8%	100.0%
	1980	28,655	7,186	750	2,484	1,531	1,084	41,690
	% of Tot	68.7%	17.2%	1.8%	6.0%	3.7%	2.6%	100.0%
	1990	38,766	6,605	570	2,619	1,121	1,892	51,573
Napa	% of Tot	75.2%	12.8%	1.1%	5.1%	2.2%	3.7%	100.0%
	2000	41,698	8,519	803	2,378	1,080	2,915	57,393
	% of Tot	72.7%	14.8%	1.4%	4.1%	1.9%	5.1%	100.0%
	1980	113,724	42,028	129,683	36,823	6,829	7,540	336,627
	% of Tot	33.8%	12.5%	38.5%	10.9%	2.0%	2.2%	100.0%
San	1990	147,187	43,925	128,160	37,611	10,947	14,479	382,309
Francisco	% of Tot	38.5%	11.5%	33.5%	9.8%	2.9%	3.8%	100.0%
	2000	169,508	45,152	130,311	39,192	15,014	19,376	418,553
	% of Tot	40.5%	10.8%	31.1%	9.4%	3.6%	4.6%	100.0%
	1980	210,558	50,577	24,137	8,093	7,561	4,907	305,833
	% of Tot	68.8%	16.5%	7.9%	2.6%	2.5%	1.6%	100.0%
San	1990	251,218	45,104	25,788	8,858	6,059	9,532	346,559
Mateo	% of Tot	72.5%	13.0%	7.4%	2.6%	1.7%	2.8%	100.0%
	2000	256,066	45,367	26,029	7,609	6,180	12,845	354,096
	% of Tot	72.3%	12.8%	7.4%	2.1%	1.7%	3.6%	100.0%
	1980	470,652	107,639	20,115	16,757	24,104	10,310	649,577
	% of Tot	72.5%	16.6%	3.1%	2.6%	3.7%	1.6%	100.0%
Santa	1990	618,995	98,163	23,727	16,509	19,225	19,986	796,605
Clara	% of Tot	77.7%	12.3%	3.0%	2.1%	2.4%	2.5%	100.0%
	2000	641,113	101,188	29,118	14,786	16,854	25,868	828,927
	% of Tot	77.3%	12.2%	3.5%	1.8%	2.0%	3.1%	100.0%
	1980	65,650	23,232	1,879	4,298	3,599	1,353	100,011
	% of Tot	65.6%	23.2%	1.9%	4.3%	3.6%	1.4%	100.0%
	1990	114,233	29,320	3,604	3,916	3,460	4,180	158,713
Solano	% of Tot	72.0%	18.5%	2.3%	2.5%	2.2%	2.6%	100.0%
	2000	127,896	30,973	4,662	2,784	2,815	5,441	174,571
	% of Tot	73.3%	17.7%	2.7%	1.6%	1.6%	3.1%	100.0%
	1980	88,591	20,829	4,093	5,422	4,391	4,358	127,684
	% of Tot	69.4%	16.3%	3.2%	4.2%	3.4%	3.4%	100.0%
	1990	142,074	24,760	4,351	6,209	3,721	9,316	190,431
Sonoma	% of Tot	74.6%	13.0%	2.3%	3.3%	2.0%	4.9%	100.0%
	2000	168,134	28,283	5,507	6,929	3,848	12,246	224,947
	% of Tot	74.7%	12.6%	2.4%	3.1%	1.7%	5.4%	100.0%
	1980	1,558,649	404,727	283,277	109,007	77,887	47,767	2,481,314
	% of Tot	62.8%	16.3%	11.4%	4.4%	3.1%	1.9%	100.0%
Bay	1990	2,104,716	399,673	293,581	111,968	69,610	106,086	3,085,634
Area	% of Tot	68.2%	13.0%	9.5%	3.6%	2.3%	3.4%	100.0%
	2000	2,248,095	426,500	321,053	106,063	71,605	132,735	3,306,051
	% of Tot	68.0%	12.9%	9.7%	3.2%	2.2%	4.0%	100.0%
Sources:   U.S. Bureau of the Census, Decennial Censuses – 1980, 1990, 2000
Summary Tape File 3A (1980-1990) and Demographic Profile 2, 3, 4 (2000)