People in McLean County are among the state's healthiest.  A recent study ranks McLean at number 18 out of the state's 102 counties when it comes to mortality and morbidity rates.  They come in at number four when it comes to how social and economic factors impact health.  That means the people there are faring better than most physically, mentally, and financially.  Plus, they're living longer to tell about it.  The study was conducted by the University of Wisconsin's Population Health Institute and the Robert Wood Johnson Foundation.  A spokesperson for the health institute says they encourage each county to look at the findings and determine how they can improve the quality of life for each of its residents.