diff --git a/app/controllers/body_trackers_controller.rb b/app/controllers/body_trackers_controller.rb
index b21dd30..2f86670 100644
--- a/app/controllers/body_trackers_controller.rb
+++ b/app/controllers/body_trackers_controller.rb
@@ -29,6 +29,8 @@ class BodyTrackersController < ApplicationController
         attrs = q.attributes.except('id', 'project_id', 'parent_id', 'lft', 'rgt',
                                     'created_at', 'updated_at')
         attrs['parent'] = q.parent ? available[[q.parent.name, q.parent.domain]] : nil
+        attrs['formula_attributes'] = q.formula.attributes.except('id', 'quantity_id',
+                                                                  'created_at', 'updated_at')
         obj = @project.quantities.create(attrs)
         available[[q.name, q.domain]] = obj
       end
diff --git a/app/views/quantities/_form.html.erb b/app/views/quantities/_form.html.erb
index 301d28c..c46498e 100644
--- a/app/views/quantities/_form.html.erb
+++ b/app/views/quantities/_form.html.erb
@@ -13,6 +13,7 @@
   <p><%= f.text_field :description, style: "width: 100%;" %></p>
   <%= f.fields_for :formula do |ff| %>
     <p><%= ff.text_field :code, placeholder: t('.formula_placeholder'),
-        style: "width: 100%;" %></p>
+      style: "width: 100%;" %></p>
+    <p><%= ff.check_box :zero_nil, {label: ''} %><%= t('.zero_nil') %></p>
   <% end %>
 </div>
diff --git a/config/locales/en.yml b/config/locales/en.yml
index 6db430e..b000a28 100644
--- a/config/locales/en.yml
+++ b/config/locales/en.yml
@@ -123,6 +123,7 @@ en:
       null_parent: '- none -'
       formula_placeholder: 'provide if value of quantity has to be computed in terms of
         other quantities'
+      zero_nil: 'substitute missing formula values with 0?'
   units:
     index:
       heading: 'Units'
diff --git a/db/migrate/002_load_defaults.rb b/db/migrate/002_load_defaults.rb
index 9830e50..1306e41 100644
--- a/db/migrate/002_load_defaults.rb
+++ b/db/migrate/002_load_defaults.rb
@@ -13,6 +13,8 @@ class LoadDefaults < ActiveRecord::Migration
         # https://www.fsai.ie/legislation/food_legislation/food_information_fic/nutrition_labelling.html
         e1 = Quantity.create project: nil, domain: :diet, parent: nil, name: "Energy",
           description: "Total energy"
+        e2 = Quantity.create project: nil, domain: :diet, parent: e1, name: "Calculated",
+          description: "Total energy calculated from macronutrients"
 
         p1 = Quantity.create project: nil, domain: :diet, parent: nil, name: "Proteins",
           description: "Total amount of proteins"
@@ -141,10 +143,9 @@ class LoadDefaults < ActiveRecord::Migration
         b9 = Quantity.create project: nil, domain: :measurement, parent: b1,
           name: "VF", description: "Visceral fat"
 
-        # Calculated quantities go at the and to make sure dependencies exist
-        e2 = Quantity.create project: nil, domain: :diet, parent: e1, name: "Calculated",
-          description: "Total energy calculated from macronutrients",
-          formula_attributes: {code: "4*Proteins + 9*Fats + 4*Carbohydrates", zero_nil: true}
+        # Formulas go at the and to make sure dependencies exist
+        e2.create_formula code: "4*Proteins + 9*Fats + 4*Carbohydrates", zero_nil: true
+        b3.create_formula code: "'% fat' * 'Weight'", zero_nil: true
 
         Source.create project: nil, name: "nutrition label",
           description: "nutrition facts taken from package nutrition label"