diff --git a/CHANGES.md b/CHANGES.md
index 3f6cfec7..4195e488 100644
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -1,9 +1,11 @@
 ## 0.8.6 (unreleased)
 
-* `health`, `missing`, and `unused` now exit with code `1` if the respective keys are detected [#151](https://github.com/glebm/i18n-tasks/issues/151).
-* XLSX report compatibility with OSX Numbers App [#159](https://github.com/glebm/i18n-tasks/issues/159).
-* RSpec template compatibility with `config.expose_dsl_globally = false` [#148](https://github.com/glebm/i18n-tasks/issues/148).
-* `bundle show vagrant` example in the config template is no longer interpolated [#161](https://github.com/glebm/i18n-tasks/issues/161).
+* Keys missing in the source are now reported in all locales from the missing task. [#162](https://github.com/glebm/i18n-tasks/issues/162)
+* Fixed `data-remove` task. [#140](https://github.com/glebm/i18n-tasks/issues/140)
+* `health`, `missing`, and `unused` now exit with code `1` if the respective keys are detected. [#151](https://github.com/glebm/i18n-tasks/issues/151)
+* XLSX report compatibility with the OSX Numbers App. [#159](https://github.com/glebm/i18n-tasks/issues/159)
+* RSpec template compatibility with `config.expose_dsl_globally = false`. [#148](https://github.com/glebm/i18n-tasks/issues/148)
+* `bundle show vagrant` example in the config template is no longer interpolated .[#161](https://github.com/glebm/i18n-tasks/issues/161)
 
 ## 0.8.5
 
diff --git a/config/locales/en.yml b/config/locales/en.yml
index 186c7fd4..3d78f73b 100644
--- a/config/locales/en.yml
+++ b/config/locales/en.yml
@@ -15,7 +15,7 @@ en:
           key_pattern_to_rename: Full key (pattern) to rename. Required
           locale: Locale
           locale_to_translate_from: Locale to translate from
-          locales_filter: "Locale(s) to process. Special: base"
+          locales_filter: 'Locale(s) to process. Special: base'
           missing_types: 'Filter by types: %{valid}'
           new_key_name: New name, interpolates original name as %{key}. Required
           nostdin: Do not read from stdin
@@ -90,7 +90,7 @@ en:
       none: No translations are missing.
     remove_unused:
       confirm:
-        one: One translations will be removed from %{locales}.
+        one: "%{count} translation will be removed from %{locales}."
         other: "%{count} translation will be removed from %{locales}."
       noop: No unused keys to remove
       removed: Removed %{count} keys
diff --git a/lib/i18n/tasks/command/commands/missing.rb b/lib/i18n/tasks/command/commands/missing.rb
index cf6c1d4c..87a1423e 100644
--- a/lib/i18n/tasks/command/commands/missing.rb
+++ b/lib/i18n/tasks/command/commands/missing.rb
@@ -49,11 +49,6 @@ def translate_missing(opt = {})
         def add_missing(opt = {})
           forest = i18n.missing_keys(opt).set_each_value!(opt[:value])
           i18n.data.merge! forest
-          # missing keys detected in the source are only returned in the base locale tree
-          # merge again in case such keys have been added to add them to other locales
-          forest_2 = i18n.missing_keys(opt).set_each_value!(opt[:value])
-          i18n.data.merge! forest_2
-          forest.merge! forest_2
           log_stderr t('i18n_tasks.add_missing.added', count: forest.leaves.count)
           print_forest forest, opt
         end
diff --git a/lib/i18n/tasks/command/commands/usages.rb b/lib/i18n/tasks/command/commands/usages.rb
index aa9e4d9c..faabf4a5 100644
--- a/lib/i18n/tasks/command/commands/usages.rb
+++ b/lib/i18n/tasks/command/commands/usages.rb
@@ -52,7 +52,7 @@ def remove_unused(opt = {})
 
         def confirm_remove_unused!(unused_keys, opt)
           return if ENV['CONFIRM'] || opt[:confirm]
-          locales = bold(opt[:locales] * ', ')
+          locales = bold(unused_keys.flat_map { |root| root.key.split('+') }.sort.uniq * ', ')
           msg     = [
               red(t('i18n_tasks.remove_unused.confirm', count: unused_keys.leaves.count, locales: locales)),
               yellow(t('i18n_tasks.common.continue_q')),
diff --git a/lib/i18n/tasks/console_context.rb b/lib/i18n/tasks/console_context.rb
index 330946d6..9441980b 100644
--- a/lib/i18n/tasks/console_context.rb
+++ b/lib/i18n/tasks/console_context.rb
@@ -36,13 +36,12 @@ def guide
         green(bold "i18n-tasks IRB Quick Start guide") + "\n" + <<-TEXT
 #{yellow 'Data as trees'}
   tree(locale)
-  missing_tree(locale, compared_to = base_locale)
   used_tree(source_occurrences: false, key_filter: nil)
   unused_tree(locale)
   build_tree('es' => {'hello' => 'Hola'})
 
 #{yellow 'Traversal'}
-  tree = missing_tree(base_locale)
+  tree = missing_diff_tree('es')
   tree.nodes { |node| }
   tree.nodes.to_a
   tree.leaves { |node| }
diff --git a/lib/i18n/tasks/data/tree/node.rb b/lib/i18n/tasks/data/tree/node.rb
index 5bfeeaee..bef0143b 100644
--- a/lib/i18n/tasks/data/tree/node.rb
+++ b/lib/i18n/tasks/data/tree/node.rb
@@ -63,7 +63,7 @@ def parent?
     end
 
     def children?
-      children && children.any?
+      children && !children.empty?
     end
 
     def data
@@ -119,6 +119,13 @@ def walk_from_root(&visitor)
       end
     end
 
+    def set(full_key, node)
+      (@children ||= Siblings.new(parent: self)).set(full_key, node)
+      dirty!
+      node
+    end
+    alias []= set
+
     def to_nodes
       Nodes.new([self])
     end
diff --git a/lib/i18n/tasks/data/tree/nodes.rb b/lib/i18n/tasks/data/tree/nodes.rb
index 2f607263..b8604302 100644
--- a/lib/i18n/tasks/data/tree/nodes.rb
+++ b/lib/i18n/tasks/data/tree/nodes.rb
@@ -79,7 +79,7 @@ def merge!(nodes)
     alias + merge!
 
     def children(&block)
-      return to_enum(:children) { map { |c| c.children.size }.reduce(:+) } unless block
+      return to_enum(:children) { map { |c| c.children ? c.children.size : 0 }.reduce(:+) } unless block
       each do |node|
         node.children.each(&block) if node.children?
       end
diff --git a/lib/i18n/tasks/data/tree/siblings.rb b/lib/i18n/tasks/data/tree/siblings.rb
index dac57d5d..52b0d216 100644
--- a/lib/i18n/tasks/data/tree/siblings.rb
+++ b/lib/i18n/tasks/data/tree/siblings.rb
@@ -1,11 +1,15 @@
 # coding: utf-8
 
+require 'set'
+require 'i18n/tasks/split_key'
 require 'i18n/tasks/data/tree/nodes'
 module I18n::Tasks::Data::Tree
   # Siblings represents a subtree sharing a common parent
   # in case of an empty parent (nil) it represents a forest
   # siblings' keys are unique
   class Siblings < Nodes
+    include ::I18n::Tasks::SplitKey
+
     attr_reader :parent, :key_to_node
 
     def initialize(opts = {})
@@ -44,8 +48,6 @@ def replace_node!(node, new_node)
       key_to_node[new_node.key] = new_node
     end
 
-    include ::I18n::Tasks::SplitKey
-
     # @return [Node] by full key
     def get(full_key)
       first_key, rest = split_key(full_key.to_s, 2)
@@ -121,15 +123,12 @@ def merge(nodes)
     end
 
     def subtract_keys(keys)
-      exclude = {}
+      to_remove = Set.new
       keys.each do |full_key|
-        if (node = get full_key)
-          exclude[node] = true
-        end
+        node = get full_key
+        to_remove << node if node
       end
-      select_nodes { |node|
-        not exclude[node] || node.children.try(:all?) { |c| exclude[c] }
-      }
+      remove_nodes_collapsing_emptied_ancestors to_remove
     end
 
     def subtract_by_key(other)
@@ -143,8 +142,6 @@ def set_root_key!(new_key, data = nil)
       self
     end
 
-    private
-
     def merge_node!(node)
       if key_to_node.key?(node.key)
         our = key_to_node[node.key]
@@ -164,6 +161,27 @@ def merge_node!(node)
       end
     end
 
+    # @param [Enumerable] nodes. Modified in-place.
+    def remove_nodes_collapsing_emptied_ancestors(nodes)
+      add_ancestors_that_only_contain_nodes! nodes
+      select_nodes { |node| !nodes.include?(node) }
+    end
+
+    # @param [Enumerable] nodes. Modified in-place.
+    def remove_nodes_collapsing_emptied_ancestors!(nodes)
+      add_ancestors_that_only_contain_nodes! nodes
+      select_nodes! { |node| !nodes.include?(node) }
+    end
+
+    private
+
+    # @param [Set] nodes. Modified in-place.
+    def add_ancestors_that_only_contain_nodes!(nodes)
+      levels.reverse_each do |level_nodes|
+        level_nodes.each { |node| nodes << node if node.children? && node.children.all? { |c| nodes.include?(c) } }
+      end
+    end
+
     def warn_add_children_to_leaf(node)
       ::I18n::Tasks::Logging.log_warn "'#{node.full_key}' was a leaf, now has children (value <- scope conflict)"
     end
diff --git a/lib/i18n/tasks/data/tree/traversal.rb b/lib/i18n/tasks/data/tree/traversal.rb
index 48afb947..0b518501 100644
--- a/lib/i18n/tasks/data/tree/traversal.rb
+++ b/lib/i18n/tasks/data/tree/traversal.rb
@@ -18,14 +18,15 @@ def leaves(&visitor)
 
       def levels(&block)
         return to_enum(:levels) unless block
-        nodes    = to_nodes
+        nodes = to_nodes
         unless nodes.empty?
           block.yield nodes
-          if nodes.children.size == 1
-            first.children
+          if nodes.size == 1
+            node = first
+            node.children.levels(&block) if node.children?
           else
-            Nodes.new(nodes: nodes.children)
-          end.levels(&block)
+            Nodes.new(nodes: nodes.children).levels(&block)
+          end
         end
         self
       end
@@ -76,7 +77,8 @@ def root_key_values(sort = false)
 
       #-- modify / derive
 
-      # @return Siblings
+      # Select the nodes for which the block returns true. Pre-order traversal.
+      # @return [Siblings] a new tree
       def select_nodes(&block)
         tree = Siblings.new
         each do |node|
@@ -90,6 +92,22 @@ def select_nodes(&block)
         tree
       end
 
+      # Select the nodes for which the block returns true. Pre-order traversal.
+      # @return [Siblings] self
+      def select_nodes!(&block)
+        to_remove = []
+        each do |node|
+          if block.yield(node)
+            node.children.select_nodes!(&block) if node.children
+          else
+            # removing during each is unsafe
+            to_remove << node
+          end
+        end
+        to_remove.each { |node| remove! node }
+        self
+      end
+
       # @return Siblings
       def select_keys(opts = {}, &block)
         root = opts.key?(:root) ? opts[:root] : false
diff --git a/lib/i18n/tasks/missing_keys.rb b/lib/i18n/tasks/missing_keys.rb
index 0312fd40..62131d9d 100644
--- a/lib/i18n/tasks/missing_keys.rb
+++ b/lib/i18n/tasks/missing_keys.rb
@@ -1,4 +1,5 @@
 # coding: utf-8
+require 'set'
 module I18n::Tasks
   module MissingKeys
 
@@ -48,20 +49,10 @@ def missing_diff_forest(locales, base = base_locale)
       tree
     end
 
-    def missing_used_forest(locales, base = base_locale)
-      if locales.include?(base)
-        missing_used_tree(base)
-      else
-        empty_forest
-      end
-    end
-
-    def missing_tree(locale, compared_to)
-      if locale == compared_to
-        missing_used_tree locale
-      else
-        missing_diff_tree locale, compared_to
-      end
+    def missing_used_forest(locales, _base = base_locale)
+      locales.inject(empty_forest) { |forest, locale|
+        forest.merge! missing_used_tree(locale)
+      }
     end
 
     # keys present in compared_to, but not in locale
@@ -96,5 +87,32 @@ def equal_values_tree(locale, compare_to = base_locale)
     def locale_key_missing?(locale, key)
       !key_value?(key, locale) && !ignore_key?(key, :missing)
     end
+
+    # @param [::I18n::Tasks::Data::Tree::Siblings] forest
+    def collapse_missing_used_locales!(forest)
+      locales_and_nodes_by_key = {}
+      to_remove                = []
+      forest.each do |root|
+        locale = root.key
+        root.leaves { |node|
+          if node.data[:type] == :missing_used
+            (locales_and_nodes_by_key[node.full_key(root: false)] ||= []) << [locale, node]
+            to_remove << node
+          end
+        }
+      end
+      forest.remove_nodes_collapsing_emptied_ancestors! to_remove
+      keys_and_nodes_by_locale = {}
+      locales_and_nodes_by_key.each { |key, locales_and_nodes|
+        locales = locales_and_nodes.map(&:first).sort.join('+')
+        (keys_and_nodes_by_locale[locales] ||= []) << [key, locales_and_nodes[0][1]]
+      }
+      keys_and_nodes_by_locale.map { |locales, keys_nodes|
+        keys_nodes.each { |(key, node)|
+          forest["#{locales}.#{key}"] = node
+        }
+      }
+      forest
+    end
   end
 end
diff --git a/lib/i18n/tasks/reports/base.rb b/lib/i18n/tasks/reports/base.rb
index ace119db..8eac4578 100644
--- a/lib/i18n/tasks/reports/base.rb
+++ b/lib/i18n/tasks/reports/base.rb
@@ -51,5 +51,14 @@ def forest_to_attr(forest)
         {key: key, value: node.value, type: node.data[:type], locale: node.root.key, data: node.data}
       }
     end
+
+    def format_locale(locale)
+      return '' unless locale
+      if locale.split('+') == task.locales.sort
+        'all'
+      else
+        locale.tr '+', ' '
+      end
+    end
   end
 end
diff --git a/lib/i18n/tasks/reports/spreadsheet.rb b/lib/i18n/tasks/reports/spreadsheet.rb
index de1c4c34..77954493 100644
--- a/lib/i18n/tasks/reports/spreadsheet.rb
+++ b/lib/i18n/tasks/reports/spreadsheet.rb
@@ -20,17 +20,19 @@ def save_report(path, opts)
     private
 
     def add_missing_sheet(wb)
-      tree = task.missing_keys
+      forest = task.missing_keys
+      forest = task.collapse_plural_nodes!(forest)
+      forest = task.collapse_missing_used_locales!(forest)
       wb.styles do |s|
         type_cell = s.add_style :alignment => {:horizontal => :center}
         locale_cell  = s.add_style :alignment => {:horizontal => :center}
         regular_style = s.add_style
-        wb.add_worksheet(name: missing_title(tree)) { |sheet|
+        wb.add_worksheet(name: missing_title(forest)) { |sheet|
           sheet.page_setup.fit_to :width => 1
           sheet.add_row [I18n.t('i18n_tasks.common.type'), I18n.t('i18n_tasks.common.locale'), I18n.t('i18n_tasks.common.key'), I18n.t('i18n_tasks.common.base_value')]
           style_header sheet
-          tree.keys do |key, node|
-            locale, type = node.root.data[:locale], node.data[:type]
+          forest.keys do |key, node|
+            locale, type = format_locale(node.root.data[:locale]), node.data[:type]
             sheet.add_row [missing_type_info(type)[:summary], locale, key, task.t(key)],
             styles: [type_cell, locale_cell, regular_style, regular_style]
           end
diff --git a/lib/i18n/tasks/reports/terminal.rb b/lib/i18n/tasks/reports/terminal.rb
index bb288b5c..2cce5059 100644
--- a/lib/i18n/tasks/reports/terminal.rb
+++ b/lib/i18n/tasks/reports/terminal.rb
@@ -9,13 +9,14 @@ class Terminal < Base
 
         def missing_keys(forest = task.missing_keys)
           forest = task.collapse_plural_nodes!(forest)
+          forest = task.collapse_missing_used_locales!(forest)
           if forest.present?
             print_title missing_title(forest)
             print_table headings: [cyan(bold(I18n.t('i18n_tasks.common.locale'))),
                                    cyan(bold I18n.t('i18n_tasks.common.key')),
                                    I18n.t('i18n_tasks.missing.details_title')] do |t|
               t.rows = sort_by_attr!(forest_to_attr(forest)).map do |a|
-                [{value: cyan(a[:locale]), alignment: :center}, cyan(a[:key]), missing_key_info(a)]
+                [{value: cyan(format_locale(a[:locale])), alignment: :center}, cyan(a[:key]), missing_key_info(a)]
               end
             end
           else
diff --git a/spec/i18n_tasks_spec.rb b/spec/i18n_tasks_spec.rb
index 5e911a40..e463ec0c 100644
--- a/spec/i18n_tasks_spec.rb
+++ b/spec/i18n_tasks_spec.rb
@@ -44,31 +44,36 @@
   end
 
   describe 'missing' do
-    let (:expected_missing_keys) {
-      %w( en.used_but_missing.key
-          en.relative.index.missing
-          es.missing_in_es.a
-          en.present_in_es_but_not_en.a
-          en.hash.pattern_missing.a
-          en.hash.pattern_missing.b
-          en.missing_symbol_key
-          en.missing_symbol.key_two
-          en.missing_symbol.key_three
-          es.missing_in_es_plural_1.a
-          es.missing_in_es_plural_2.a
-          en.missing-key-with-a-dash.key
-          en.missing-key-question?.key
-          en.fn_comment
-          en.only_in_es
-          en.events.show.success
-        )
+    let (:expected_missing_keys_in_source) {
+      %w(
+        used_but_missing.key
+        relative.index.missing
+        hash.pattern_missing.a
+        hash.pattern_missing.b
+        missing_symbol_key
+        missing_symbol.key_two
+        missing_symbol.key_three
+        missing-key-with-a-dash.key
+        missing-key-question?.key
+        fn_comment
+        events.show.success
+      )
+    }
+    let (:expected_missing_keys_diff) {
+      %w(
+        es.missing_in_es.a
+        en.present_in_es_but_not_en.a
+        es.missing_in_es_plural_1.a
+        es.missing_in_es_plural_2.a
+        en.only_in_es
+      )
     }
     it 'detects missing' do
-      es_keys = expected_missing_keys.grep(/^es\./)
+      es_keys = expected_missing_keys_diff.grep(/^es\./) + expected_missing_keys_in_source.map { |k| "es.#{k}" }
       out, result = run_cmd_capture_stdout_and_result 'missing'
       expect(result).to eq :exit_1
-      expect(out).to be_i18n_keys expected_missing_keys
-      # locale argument
+      expect(out).to be_i18n_keys(expected_missing_keys_diff +
+                                      expected_missing_keys_in_source.map { |k| "all.#{k}" })
       expect(run_cmd 'missing', '-les').to be_i18n_keys es_keys
       expect(run_cmd 'missing', 'es').to be_i18n_keys es_keys
     end
diff --git a/spec/support/i18n_tasks_output_matcher.rb b/spec/support/i18n_tasks_output_matcher.rb
index 184df2c3..4bb3d320 100644
--- a/spec/support/i18n_tasks_output_matcher.rb
+++ b/spec/support/i18n_tasks_output_matcher.rb
@@ -8,14 +8,13 @@ def extract_keys(actual)
     actual = Term::ANSIColor.uncolor(actual).split("\n").map(&:presence).compact
     actual = actual[3..-2]
     actual = actual.map { |row|
-      next if row =~ /^\|\s+\|/
-      row.gsub(/(?:\s|^)\|(?:\s|$)/, ' ').gsub(/\s+/, ' ').strip.split(' ').map(&:presence).compact
+      row[1..-1].gsub(/(?:\s+|^)\|(?:\s+|$)/, '|').gsub(/\s+/, ' ').strip.split(/\s*\|\s*/)
     }.compact
     return [] if actual.empty?
     locale_col = 0
     key_col = 1
     actual.map { |row|
-      key = "#{row[locale_col]}.#{row[key_col]}"
+      key = [row[locale_col], row[key_col]].map(&:presence).compact.join('.')
       key = key[0..-2] if key.end_with?(':')
       key
     }.compact