Table 3. Market Share of Physician Organizations, by Number of Assigned Medicare Fee-for-Service Beneficiaries Residing in the Boston Metropolitan Statistical Area: 2002.

Number of Assigned Beneficiaries	Number of Organizations	Market Share1	Cumulative Market Share
		Percent
10,000 or More	1	5.0	5.0
5,000-9,999	4	9.6	14.6
2,500-4,999	13	13.2	27.8
1,000-2,499	31	14.9	42.7
500-999	53	9.9	52.6
250-499	94	9.0	61.6
100-249	431	19.2	80.8
1-99	7,725	19.2	100.0

¹Market share is share of total number of assigned beneficiaries.

SOURCE: Pope, G.C. and Kautter, J., RTI International, Waltham, MA.