7,166 -- That's the number of housing units on Long Island whose residents have no vehicle and lack easy access to a supermarket, according to figures based on the recent census. Most of them are considered to be in a "food desert," meaning they're located in low-income areas where the nearest supermarket is more than a mile away. The number may seem small, but it shows that not everyone in our comfortable suburb can get healthy and affordable foods. Farmers markets have been targeting such areas, but clearly there's more to be done.