The median age in Pima County was 32.8 in 1990 (slightly below the national average), 35.7 in 2000 and was estimated as 36.7 in 2007. The slow rise of the median age is due to the aging of the Baby Boomers, not to any massive influx of seniors. Much of metropolitan Tucson's growth over the next 20 years will be driven by working age people moving here for employment opportunities.

	Male	Female	Total
0-4	35,701	33,965	69,666
5-9	33,472	32,248	65,720
10-14	34,220	32,443	66,663
15-19	37,126	35,534	72,660
20-24	38,195	36,764	74,959
25-29	35,389	35,339	70,728
30-34	32,918	31,824	64,742
35-39	32,033	32,619	64,652
40-44	33,801	34,491	68,292
45-49	34,891	36,711	71,602
50-54	31,985	34,782	66,767
55-59	29,796	31,842	61,638
60-64	22,288	25,171	47,459
65-69	17,457	20,617	38,074
70-74	15,503	18,383	33,886
75-79	13,487	17,234	30,721
80-84	9,852	14,294	24,146
85+	7,689	13,509	21,198
Total	495,803	517,770	1,013,573

Source: Arizona Department of Health Services