Regarding the park district referendum in Arlington Heights, the Cook County Treasurer has a link to the financial statements for all government entities in the county. For 2011, the AHPD had $31.5 million in current assets. They had $9.7 million in current liabilities. For financial types, that is a current ratio of 3.3. Most private businesses average about 1.5.
Compared to a well-run business, AHPD has $15 million more in current assets than it needs to responsibly meet its current liabilities. This money represents the accumulation over time of taxes collected in excess of expenses.
The library is also interesting. The AHPL has $19.8 million in current assets versus $1.2 million in current liabilities. Assuming you need to keep a couple million around for a rainy day, the library has at least $16 million in excess taxation accumulated.