As an eighth-grade math teacher in Palatine, I take issue with Jake Griffin's interesting but incomplete explanation of the increase in tax levies in a recent front-page article. He reported that a Daily Herald analysis of Illinois Department of Revenue reports from 2010 and 2005 shows a $2.2 billion increase in school district levies for the Chicago metro area.
As a property taxpayer, I agree that a $2.2 billion increase is large. But as a math educator, I wondered what percent of an increase that amount represented. For example, if 2005 levies were $11 billion then the increase would mean a 20 percent rise and something to be alarmed about. However, if levies in 2005 were $220 billion, the increase would be only a 1 percent rise. That would be quite a difference in the nature of the increase, suggesting that school districts are holding the line on spending.
When I teach my students about math and percents in particular, I remind them of the adage that there are "lies, damned lies and statistics." Without a percent context to understand what numbers represent, they are just getting statistics and not understanding the full picture.
I hope in the future you will include such context so that your readers don't make a wrong and incomplete conclusion.