301 Water resources	302 Conservation and land management	303 Recreational resources	304 Pollution control and abatement	306 Other natural resources
1947	2,132	1,162	156	0	71
1948	2,741	1,131	181	0	65
1949	4,040	1,457	231	0	81
1950	4,695	3,350	349	0	102
1951	4,770	3,156	337	0	108
1952	2,915	4,330	383	0	122
1953	4,755	3,259	364	0	142
1954	2,377	3,524	2,855	0	152
1955	2,152	3,105	3,021	0	329
1956	3,932	3,166	505	0	375
1957	4,414	3,544	581	0	398
1958	5,103	4,025	666	0	417
1959	5,436	4,606	780	0	530
1960	5,553	5,350	712	0	519
1961	6,134	5,213	800	0	268
1962	6,587	4,687	844	0	665
1963	7,287	4,412	995	0	690
1964	7,362	4,742	1,124	0	677
1965	5,584	7,049	1,188	0	800
1966	8,023	5,905	1,290	0	810
1967	5,828	6,635	1,452	0	1,206
1968	7,428	6,099	1,634	0	423
1969	7,908	4,284	1,506	0	648
1970	6,292	4,576	1,420	1,006	468
1971	6,887	4,803	1,751	2,562	497
1972	7,225	4,742	1,830	2,664	534
1973	7,212	4,771	1,906	3,725	562
1974	6,199	2,363	2,066	6,342	1,554
1975	6,613	3,677	2,333	7,133	2,155
1976	7,244	1,965	1,952	8,102	2,354
1977	7,895	1,808	2,059	10,514	2,374
1978	7,890	2,826	2,776	9,118	2,647
1979	8,195	2,276	2,635	10,012	2,693
1980	8,249	2,633	2,680	10,763	2,745
1981	7,358	2,653	2,310	9,206	2,632
1982	6,570	2,272	1,920	8,341	2,528
1983	6,223	2,849	1,865	6,796	2,468
1984	6,257	2,483	1,951	6,217	2,452
1985	6,134	2,768	1,848	6,645	2,482
1986	5,872	2,542	1,674	7,021	2,712
1987	5,350	2,577	1,718	6,886	2,369
1988	5,525	3,546	1,743	6,618	2,572
1989	5,320	5,001	1,779	6,433	2,493
1990	5,594	5,122	1,779	6,571	2,644
1991	5,341	5,684	1,883	7,171	2,628
1992	5,435	6,280	2,016	7,257	2,885
1993	4,958	6,402	2,212	7,070	2,925
1994	5,119	6,617	2,123	6,901	3,204
1995	5,163	6,702	2,187	7,266	3,130
1996	4,964	6,579	2,093	6,761	3,143
1997	4,735	6,159	2,116	6,750	3,012
1998	4,919	6,572	2,218	6,793	3,087
1999	4,937	6,687	2,751	7,203	3,449
2000	5,198	6,926	2,609	7,573	3,303
2001	5,377	7,489	2,331	7,661	3,477