diff --git a/book.py b/book.py
index c81afb7..f438d5d 100644
--- a/book.py
+++ b/book.py
@@ -59,6 +59,9 @@ class Book(SymbolMixin, metaclass=PoolMeta):
         }, depends=DEPENDS2+['feature', 'lines', 'asset_uomcat'])
     symbol = fields.Function(fields.Char(string='Symbol', readonly=True),
         'on_change_with_symbol')
+    asset_symbol = fields.Function(fields.Many2One(string='Symbol',
+        readonly=True, model_name='cashbook.book'),
+        'on_change_with_asset_symbol')
     quantity = fields.Function(fields.Numeric(string='Quantity',
         help='Quantity of assets until to date', readonly=True,
         digits=(16, Eval('quantity_digits', 4)),
@@ -238,6 +241,13 @@ class Book(SymbolMixin, metaclass=PoolMeta):
                 result[name][record[0]] = values[name]
         return result
 
+    @fields.depends('id')
+    def on_change_with_asset_symbol(self, name=None):
+        """ get current cashbook to enable usage of 'symbol'
+            in the form
+        """
+        return self.id
+
     @fields.depends('quantity_uom', 'currency')
     def on_change_with_symbol(self, name=None):
         """ get symbol for asset
diff --git a/line.py b/line.py
index 88b5964..b39b495 100644
--- a/line.py
+++ b/line.py
@@ -34,7 +34,9 @@ class Line(metaclass=PoolMeta):
         digits=(16, If(
             Eval('currency_digits', 2) > Eval('quantity_digits', 2),
             Eval('currency_digits', 2), Eval('quantity_digits', 2))),
-        depends=['currency_digits', 'quantity_digits']),
+        states={
+            'invisible': Eval('feature', '') != 'asset',
+        }, depends=['currency_digits', 'quantity_digits', 'feature']),
         'on_change_with_asset_rate')
 
     @fields.depends('quantity', 'amount', 'currency_digits', 'quantity_digits')
@@ -56,7 +58,8 @@ class Line(metaclass=PoolMeta):
         """ get quantity-unit of asset
         """
         if self.cashbook:
-            return self.cashbook.quantity_uom.id
+            if self.cashbook.quantity_uom:
+                return self.cashbook.quantity_uom.id
 
     @fields.depends('cashbook', '_parent_cashbook.quantity_digits')
     def on_change_with_quantity_digits(self, name=None):
diff --git a/locale/de.po b/locale/de.po
index 1ba5d0e..11e068f 100644
--- a/locale/de.po
+++ b/locale/de.po
@@ -50,6 +50,10 @@ msgctxt "field:cashbook.book,symbol:"
 msgid "Symbol"
 msgstr "Symbol"
 
+msgctxt "field:cashbook.book,asset_symbol:"
+msgid "Symbol"
+msgstr "Symbol"
+
 msgctxt "field:cashbook.book,quantity:"
 msgid "Quantity"
 msgstr "Anzahl"
diff --git a/locale/en.po b/locale/en.po
index c54ba44..870dabd 100644
--- a/locale/en.po
+++ b/locale/en.po
@@ -42,6 +42,10 @@ msgctxt "field:cashbook.book,symbol:"
 msgid "Symbol"
 msgstr "Symbol"
 
+msgctxt "field:cashbook.book,asset_symbol:"
+msgid "Symbol"
+msgstr "Symbol"
+
 msgctxt "field:cashbook.book,quantity:"
 msgid "Quantity"
 msgstr "Quantity"
diff --git a/view/book_form.xml b/view/book_form.xml
index 22f21ed..8d98082 100644
--- a/view/book_form.xml
+++ b/view/book_form.xml
@@ -26,8 +26,7 @@ full copyright notices and license terms. -->
             <label name="diff_percent" xalign="0.0" string="%" xexpand="1"/>
         </group>
         <label name="current_rate"/>
-        <field name="current_rate"/>
-
+        <field name="current_rate" symbol="asset_symbol"/>
     </xpath>
 
     <xpath expr="/form/notebook/page[@id='pggeneral']" position="after">