diff --git a/tests/data/imports.yml b/tests/data/imports.yml
index d33e009..42bb022 100644
--- a/tests/data/imports.yml
+++ b/tests/data/imports.yml
@@ -2,62 +2,62 @@
   importer: patreon.IncomeImporter
   expect:
     - payee: Alex Jones
-      date: [2017, 9, 1]
-      amount: "150.00"
+      date: !!python/object/apply:datetime.date [2017, 9, 1]
+      amount: !!python/object/apply:decimal.Decimal ["150.00"]
       currency: USD
     - payee: Dakota Doe
-      date: [2017, 9, 1]
-      amount: "12.00"
+      date: !!python/object/apply:datetime.date [2017, 9, 1]
+      amount: !!python/object/apply:decimal.Decimal ["12.00"]
       currency: USD
 
 - source: PatreonEarnings.csv
   importer: patreon.PatreonFeeImporter
   expect:
     - payee: Patreon
-      date: [2017, 9, 1]
-      amount: "61.73"
+      date: !!python/object/apply:datetime.date [2017, 9, 1]
+      amount: !!python/object/apply:decimal.Decimal ["61.73"]
       currency: USD
     - payee: Patreon
-      date: [2017, 10, 1]
-      amount: "117.03"
+      date: !!python/object/apply:datetime.date [2017, 10, 1]
+      amount: !!python/object/apply:decimal.Decimal ["117.03"]
       currency: USD
 
 - source: PatreonEarnings.csv
   importer: patreon.CardFeeImporter
   expect:
     - payee: Patreon
-      date: [2017, 9, 1]
-      amount: "52.47"
+      date: !!python/object/apply:datetime.date [2017, 9, 1]
+      amount: !!python/object/apply:decimal.Decimal ["52.47"]
       currency: USD
     - payee: Patreon
-      date: [2017, 10, 1]
-      amount: "99.47"
+      date: !!python/object/apply:datetime.date [2017, 10, 1]
+      amount: !!python/object/apply:decimal.Decimal ["99.47"]
       currency: USD
 
 - source: PatreonVat.csv
   importer: patreon.VATImporter
   expect:
     - payee: Patreon
-      date: [2017, 9, 1]
-      amount: "2.00"
+      date: !!python/object/apply:datetime.date [2017, 9, 1]
+      amount: !!python/object/apply:decimal.Decimal ["2.00"]
       currency: USD
       country_code: AT
       country_name: Austria
     - payee: Patreon
-      date: [2017, 9, 1]
-      amount: "3.30"
+      date: !!python/object/apply:datetime.date [2017, 9, 1]
+      amount: !!python/object/apply:decimal.Decimal ["3.30"]
       currency: USD
       country_code: BE
       country_name: Belgium
     - payee: Patreon
-      date: [2017, 10, 1]
-      amount: "0.40"
+      date: !!python/object/apply:datetime.date [2017, 10, 1]
+      amount: !!python/object/apply:decimal.Decimal ["0.40"]
       currency: USD
       country_code: BG
       country_name: Bulgaria
     - payee: Patreon
-      date: [2017, 10, 1]
-      amount: "6.05"
+      date: !!python/object/apply:datetime.date [2017, 10, 1]
+      amount: !!python/object/apply:decimal.Decimal ["6.05"]
       currency: USD
       country_code: CZ
       country_name: Czech Republic
@@ -66,18 +66,18 @@
   importer: stripe.PaymentImporter
   expect:
     - payee: Dakota Smith
-      date: [2017, 11, 8]
-      amount: "100.00"
-      fee: "3.0"
-      tax: "0.0"
+      date: !!python/object/apply:datetime.date [2017, 11, 8]
+      amount: !!python/object/apply:decimal.Decimal ["100.00"]
+      fee: !!python/object/apply:decimal.Decimal ["3"]
+      tax: !!python/object/apply:decimal.Decimal ["0"]
       currency: USD
       payment_id: ch_oxuish6phae2Raighooghi3U
       description: "Payment for invoice #102"
     - payee: Dakota Jones
-      date: [2017, 10, 28]
-      amount: "50.00"
-      fee: "1.4"
-      tax: "0.0"
+      date: !!python/object/apply:datetime.date [2017, 10, 28]
+      amount: !!python/object/apply:decimal.Decimal ["50.00"]
+      fee: !!python/object/apply:decimal.Decimal ["1.4"]
+      tax: !!python/object/apply:decimal.Decimal ["0"]
       currency: USD
       payment_id: ch_hHee9ef1aeyee1ruo7ochee9
       description: "Payment for invoice #100"
@@ -86,12 +86,12 @@
   importer: nbpy2017.Payment2017Importer
   expect:
     - payee: Python Person A
-      date: [2017, 10, 19]
-      amount: "80.00"
-      tickets_sold: "1.0"
-      ticket_rate: "21.25"
-      shirts_sold: "1.0"
-      shirt_rate: "25.50"
+      date: !!python/object/apply:datetime.date [2017, 10, 19]
+      amount: !!python/object/apply:decimal.Decimal ["80.00"]
+      tickets_sold: !!python/object/apply:decimal.Decimal ["1"]
+      ticket_rate: !!python/object/apply:decimal.Decimal ["21.25"]
+      shirts_sold: !!python/object/apply:decimal.Decimal ["1"]
+      shirt_rate: !!python/object/apply:decimal.Decimal ["25.50"]
       currency: USD
       invoice_id: "83"
       payment_id: ch_ahr0ue8lai1ohqu4Gei4Biem
@@ -101,12 +101,12 @@
   importer: nbpy2017.Payment2017Importer
   expect:
     - payee: Python Person B
-      date: [2017, 12, 3]
-      amount: "50.00"
-      tickets_sold: "1.0"
-      ticket_rate: "42.50"
-      shirts_sold: "0.0"
-      shirt_rate: "25.50"
+      date: !!python/object/apply:datetime.date [2017, 12, 3]
+      amount: !!python/object/apply:decimal.Decimal ["50.00"]
+      tickets_sold: !!python/object/apply:decimal.Decimal ["1"]
+      ticket_rate: !!python/object/apply:decimal.Decimal ["42.50"]
+      shirts_sold: !!python/object/apply:decimal.Decimal ["0"]
+      shirt_rate: !!python/object/apply:decimal.Decimal ["25.50"]
       currency: USD
       payment_id: ch_eishei9aiY8aiqu4lieYiu9i
       stripe_id: ch_eishei9aiY8aiqu4lieYiu9i
@@ -116,12 +116,12 @@
   importer: nbpy2017.Payment2017Importer
   expect:
     - payee: Python Person C
-      date: [2017, 10, 5]
-      amount: "55.00"
-      tickets_sold: "1.0"
-      ticket_rate: "21.25"
-      shirts_sold: "1.0"
-      shirt_rate: "25.50"
+      date: !!python/object/apply:datetime.date [2017, 10, 5]
+      amount: !!python/object/apply:decimal.Decimal ["55.00"]
+      tickets_sold: !!python/object/apply:decimal.Decimal ["1"]
+      ticket_rate: !!python/object/apply:decimal.Decimal ["21.25"]
+      shirts_sold: !!python/object/apply:decimal.Decimal ["1"]
+      shirt_rate: !!python/object/apply:decimal.Decimal ["25.50"]
       currency: USD
       payment_id: ch_daer0ahwoh9oDeiqu2eimoD7
       stripe_id: ch_daer0ahwoh9oDeiqu2eimoD7
diff --git a/tests/test_importers.py b/tests/test_importers.py
index 1639009..b5bca5c 100644
--- a/tests/test_importers.py
+++ b/tests/test_importers.py
@@ -12,23 +12,6 @@ from import2ledger import importers
 from . import DATA_DIR
 
 class TestImporters:
-    def _value_converter(value):
-        try:
-            is_decimal = re.match(r'^[-+]?\d+\.\d+$', value)
-        except TypeError:
-            is_decimal = False
-        if is_decimal:
-            return decimal.Decimal
-        else:
-            return lambda x: x
-
-    def _date(parts_list):
-        return datetime.date(*parts_list)
-
-    KEY_CONVERTERS = {
-        'date': _date,
-    }
-
     with pathlib.Path(DATA_DIR, 'imports.yml').open() as yaml_file:
         test_data = yaml.load(yaml_file)
     for test in test_data:
@@ -38,14 +21,6 @@ class TestImporters:
         module = importlib.import_module('.' + module_name, 'import2ledger.importers')
         test['importer'] = getattr(module, class_name)
 
-        for expect_result in test['expect']:
-            for key, value in expect_result.items():
-                try:
-                    convert_func = KEY_CONVERTERS[key]
-                except KeyError:
-                    convert_func = _value_converter(value)
-                expect_result[key] = convert_func(value)
-
     @pytest.mark.parametrize('source_path,importer', [
         (t['source'], t['importer']) for t in test_data
     ])