Revert "Kill dead code"

This reverts commit 48138d0b6e.

lib/mutant/reporter/cli/printer.rb

@@ -231,6 +231,16 @@ module Mutant
             coverage * 100
           end
 
+          # Return overhead percent
+          #
+          # @return [Float]
+          #
+          # @api private
+          #
+          def overhead_percent
+            (overhead / killtime) * 100
+          end
+
         end # EnvProgress
 
         # Full env result reporter
@@ -252,6 +262,16 @@ module Mutant
 
         private
 
+          # Return coverage percent
+          #
+          # @return [Float]
+          #
+          # @api private
+          #
+          def coverage_percent
+            coverage * 100
+          end
+
           # Return overhead percent
           #
           # @return [Float]