Color Coding Scheme for MCDC Basic Tables Reports
Beginning with Version 2 of the Missouri Census Data
Center's Basic Tables report generator we have identified several dozen data
items as key indicators. We felt it would help users to interpret the
report if they could get a quick visual indication as to how key items were ranked.
For example, the Average Household Income variable is a good indictor of the
economic well being of an area.
But most non-economists would have a hard time telling you whether a value of $25,000
for this indicator was considered high, low, or somewhere in between.
This is where the color-coding scheme is designed to help. We ran statistical
summaries of selected indicators, storing a series of percentile cutoff points for
each indicator / geographic level. For example, for states we created a
summary at the whole U.S. level based on the 51 state level summaries. For counties we
used all 3100+ counties to determine the percentile break points for the indicators.
For example, our summary data sets told us that for the Average Household Income indicator
at the county level, the 95th percentile break was at $44,186. Only 5% of the
counties in the U.S. had a value larger than this. We would use this information to
"color code" the Average Household Income cell a dark green whenever we were reporting for
a county with a value larger than $44,186.
We only used national statistics for the state and county geographic levels. For
the smaller geographies we used state data to form the percentile distributions. So,
at the census tract level for Missouri we have statistics on the distribution of each of
the indicators and we use these whenever we generate a report for a census tract (or BNA)
in the state of Missouri. We use a different set of numbers for Illinois, another for
California, etc. So if you see that the Percent of Persons below poverty is shaded
dark green for a census tract in Pennsylvania, it means that the value is more than the 95-
percentile number for that state (approximately 36.3%). This would be an extremely
high poverty rate, at least by the standards of the state of Pennsylvania.
Key Indicator Cell Coding Scheme
||Dark red indicates a very low value, less than the 5th percentile
||This pale shade of red indicates a somewhat low value, between
the 5th and 25th percentiles
||This light gray indicates a neutral value, between the 25th and 75th percentiles
||This light green color indicates a somewhat high value, between
the 75th and 95th percentiles
||This dark green color indicates a very high value, over the
| ||Any cell with a white background is not being used as an indicator
There are over 220 data items on a Basic Tables report and we chose
only 72 to classify as indictors. (We generally did not use any absolute
count items as indicators, since they would mostly just show areas that were very
large or small rather than indicating anything about the actual characteristics
of the area.)
Printing Note for IE Users
If you want to see the cell color coding in printed versions of these reports generated from
Microsoft Internet Explorer you will need to make sure that a printing option is set. Go to
the Tools/Internet Options/Advanced page. Scroll down to the "Printing Options" section and
make sure that the option Print background colors and images is checked. As far as we
can tell there is no such option in Netscape (4.7), which will always print the backgound
Please send questions or comments to Glenn Rice.