Locating appropriate data can be difficult. Census data are helpful, but often they are not current or specific enough to support an emerging need. When a community has a low unemployment rate during the year of the census, for example, but then unemployment rates steadily rise over the next several years, census data can actually harm your case for a job-training program. While your local United Way may collect the data, they often must rely on information provided by member organizations, and generally the United Way does not verify those numbers.
Individual and specific organizations are generally the best source for reliable data. For instance, if you need to know how many students receive the federal lunch program in a school district, you simply have to call the central district office to find out. Call the police department for crime statistics; the juvenile court for teen delinquency rates; or the YWCA for domestic-abuse cases.
Sometimes you'll just have to estimate. In those cases, tell the reader how you arrived at your estimate. For instance, to determine the number of prostitutes in a city, first find out the number of men and women arrested for prostitution. Go over the list with the police officers who cover the area where prostitutes are known to hang out. They will tell you which of the arrests are repeat offenders and will also provide you a more accurate estimate than the arrest numbers indicate. You'd write something like, “In 2002, the police made more than 300 arrests of approximately 280 women and 20 men. Officers working with the population estimate that the number of active prostitutes on city streets and in known houses of prostitution is between 500 and 700 people.”
Another good source of data can be a local or nearby university. Telephone the social sciences department and ask to speak to a researcher. Some really helpful university departments will assign graduate students to help you update old data or extrapolate pieces of data from aggregates.
You can also clip newspaper articles that you encounter throughout the year that may be related to the people your organization reaches. The reporter has already gathered the data to support his or her article, so you can just clip the information and file it in a notebook, saving it for later so you have a source to go to the next time you need data for a grant proposal.