Table 1. Sample Distribution to Match Populations in Data Collection Regions.

Region	Site	States Represented	U.S. Total (%)	Sample Size
I. Pacific West	Phoenix, AZ	WA, OR, ID, MT, WY, CA, NV, AZ, CO, UT, NM	21.95	198
II. North Central	Chicago, IL	MN, IA, MO, ND, SD, NE, KS, WI, IL, MI, IN, OH, KY	24.48	220
III. Northeast	Rockville, MD	ME, NH, VT, MA, RI, CT, NY, NJ, PA, DE, MD, WV, VA, DC	24.72	222
IV. South	Fort Worth, TX	TN, NC, SC, GA, FL, AL, MS, TX, OK, AR, LA	28.85	260
Total			100.00	900