Michael Barry (PDF):

MMSD financial results for 2012-13 were favorable in comparison to budget expectations. The General Fund Balance, which was budgeted to decrease by ($5.5) million to support several one-time expenditures, actually decreased by just ($1.6) million. This puts the District’s balance sheet in a stronger opening position for 2013-14. The primary reason for the favorable result was an unbudgeted revenue influx of $3.2 million from Medicaid reimbursements.
However, the Food Service Fund struggled in 2012-13, recording a net loss of $386,000 on total revenues of $10.5 million. Labor cost overages were the primary cause of the net loss. The Business Office is working closely with the Food Service department on budgetary expectations for 2013-14. Overall participation in the program decreased slightly last year.
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Open enrollment results show 370 students enrolling in to MMSD from elsewhere and 1,206 MMSD residents enrolling outside of the district. The net out is -836. (Enrollment background data & District statistics)
(Last year, MMSD had 379 students enrolling in and 1,118 enrolling out, for a net out of -739.)

Much more on open enrollment here.
Suburban Districts vs. Madison, 1995-2012.
Madison School District: Private/Parochial, Open Enrollment Leave, Open Enrollment Enter, Home Based Parent Surveys (June, 2009).