           singleParameterConfiguration(modelingResults, paramKey)
 
       # @param paramKey the modeling parameter key
+      # @param precision the minimum number of decimals to display
       # @returns the tooltip HTML content generator function
-      tooltipGenerator = (paramKey) ->
-         # The tooltip value heading.
-         if paramKey is 'kTrans'
+      tooltipGenerator = (paramKey, precision) ->
+        # The tooltip displays three decimals more than the
+        # minimum.
+        valueFormatter = d3.format(".#{ precision + 3 }f")
+
+        # The ktrans tooltip shows the FXL, FXR and delta.
+        kTransTooltipGenerator = ->
            propertyFormatter = (modelingResult, property) ->
              dspConf = Modeling.properties[property]
              # The value to display.

             "<table>" +
               rows.join("\n") +
             "</table>"
         else
           dspConf = Modeling.properties[paramKey]
           generateTooltip = (obj) ->
             # The value to display.
             value = obj.series[0].value
             "#{ dspConf.html }: #{ valueFormatter(value) }"
          
          # Return the generator function.
          generateTooltip
      
      # Configures the D3 chart with the given format. The format is an
      # object in the form {label: string, data: array}

        # Start with a copy of the shared configuration.
        conf = _.cloneDeep(COMMON_CONFIG)
        # The parameter-specific configuration.
        paramConf = parameterConfiguration(modelingResults, paramKey)
        # Add the parameter-specific settings.
        _.merge(conf, paramConf)

