Chapter 2	PM 2.5 Air Quality Data		Table 2-16			

Air Basin*	Year	Maximum 24-Hour Concentration (µg/m3)	98th Percentile 24-Hour Concentration (µg/m3)**	98th Percentile Concentration Valid?**	Average of Quarters (µg/m3)**	Average of Quarters Valid?**
Great Basin Valleys	1999	40.7	30.9	N	7.2	N
	2000	68.0	67.0	Y	18.0	N
	2001	76.0	41.0	N	10.3	N
Lake County	1999	14.5	14.5	N	4.3	N
	2000	9.4	9.4	N	4.0	N
	2001	15.1	11.3	Y	4.2	Y
Lake Tahoe	1999	21.0	21.0	Y	8.3	Y
	2000	23.0	21.0	Y	7.8	Y
	2001	31.0	26.0	Y	8.2	Y
Mojave Desert	1999	47.6	23.5	Y	11.9	Y
	2000	38.6	26.4	N	11.9	Y
	2001	35.0	29.0	N	11.5	Y
Mountain Counties	1999	92.0	84.0	Y	13.3	N
	2000	48.0	44.0	N	10.6	N
	2001	120.0	43.0	Y	15.6	Y
North Central Coast	1999	31.4	23.6	N	9.8	N
	2000	26.4	21.5	N	7.9	N
	2001	25.6	23.1	N	9.1	N
North Coast	1999	36.9	27.7	Y	9.1	Y
	2000	24.0	21.5	Y	9.1	Y
	2001	38.3	29.0	Y	9.4	Y
Northeast Plateau	1999	40.0	27.0	Y	7.9	Y
	2000	38.0	37.0	Y	8.5	Y
	2001	35.0	35.0	N	7.6	N
Sacramento Valley	1999	108.0	71.0	Y	23.7	N
	2000	98.0	70.0	Y	15.8	Y
	2001	72.0	56.0	Y	13.0	Y
Salton Sea	1999	52.5	43.2	N	15.2	Y
	2000	84.2	56.0	Y	16.9	Y
	2001	60.2	50.4	N	14.9	N
San Diego	1999	64.3	45.1	N	18.0	Y
	2000	66.3	48.7	N	15.8	Y
	2001	60.0	40.8	Y	17.7	Y
San Francisco Bay Area	1999	90.5	53.8	N	28.1	N
	2000	67.2	55.3	Y	13.6	Y
	2001	107.5	56.0	Y	12.5	Y
San Joaquin Valley	1999	136.0	120.0	Y	27.7	Y
	2000	160.0	108.0	Y	25.5	N
	2001	154.7	120.6	Y	22.5	Y
South Central Coast	1999	64.6	35.4	Y	13.8	Y
	2000	55.3	42.4	N	14.8	N
	2001	57.6	50.7	Y	14.9	Y
South Coast	1999	121.4	85.6	Y	31.0	Y
	2000	119.6	83.0	Y	28.3	Y
	2001	98.0	74.3	Y	31.0	Y

"*  The table lists the highest value for each statistic.  Within an air basin, the highest value for each statistic may reflect a different site."
"** These statistics and determination of their validity are calculated according to the methods specified in 40 CFR Part 50, Appendix N.  Validity is based on the number of measurements"
"available per quarter and therefore, depends on completeness.  Both the 98th percentile concentration and the average of quarters concentration relate to the national PM2.5 standards,"
while only the average of quarters concentration relates to the State PM2.5 standard.