diff --git a/jira_agile_metrics/calculators/cycletime.py b/jira_agile_metrics/calculators/cycletime.py
index 94bbcb6..d816a07 100644
--- a/jira_agile_metrics/calculators/cycletime.py
+++ b/jira_agile_metrics/calculators/cycletime.py
@@ -116,12 +116,12 @@ def write(self):
 
 def calculate_cycle_times(
     query_manager,
-    cycle,                  # [{name:"", statuses:[""], type:""}]
-    attributes,             # [{key:value}]
-    committed_column,       # "" in `cycle`
-    done_column,            # "" in `cycle`
-    queries,                # [{jql:"", value:""}]
-    query_attribute=None,   # ""
+    cycle,  # [{name:"", statuses:[""], type:""}]
+    attributes,  # [{key:value}]
+    committed_column,  # "" in `cycle`
+    done_column,  # "" in `cycle`
+    queries,  # [{jql:"", value:""}]
+    query_attribute=None,  # ""
     now=None,
 ):
 
diff --git a/jira_agile_metrics/calculators/cycletime_test.py b/jira_agile_metrics/calculators/cycletime_test.py
index 2e49056..36df9be 100644
--- a/jira_agile_metrics/calculators/cycletime_test.py
+++ b/jira_agile_metrics/calculators/cycletime_test.py
@@ -50,7 +50,8 @@ def jira(custom_fields):
                         [("Flagged", None, "Impediment", "customfield_100")],
                     ),
                     Change(
-                        "2018-01-03 01:00:00", [("Flagged", "Impediment", "", "customfield_100")]
+                        "2018-01-03 01:00:00",
+                        [("Flagged", "Impediment", "", "customfield_100")],
                     ),  # blocked 1 day in the backlog
                     # (doesn't count towards blocked days)
                     Change(
@@ -64,13 +65,16 @@ def jira(custom_fields):
                         ],
                     ),
                     Change(
-                        "2018-01-04 10:01:01", [("Flagged", "", "Impediment", "customfield_100")]
+                        "2018-01-04 10:01:01",
+                        [("Flagged", "", "Impediment", "customfield_100")],
                     ),
                     Change(
-                        "2018-01-05 08:01:01", [("Flagged", "Impediment", "", "customfield_100")]
+                        "2018-01-05 08:01:01",
+                        [("Flagged", "Impediment", "", "customfield_100")],
                     ),  # was blocked 1 day
                     Change(
-                        "2018-01-08 10:01:01", [("Flagged", "", "Impediment", "customfield_100")]
+                        "2018-01-08 10:01:01",
+                        [("Flagged", "", "Impediment", "customfield_100")],
                     ),  # stays blocked until today
                 ],
             ),
@@ -178,7 +182,14 @@ def jira(custom_fields):
                     ),
                     Change(
                         "2018-01-07 01:01:01",
-                        [("Flagged", None, "Awaiting input", "customfield_100")],
+                        [
+                            (
+                                "Flagged",
+                                None,
+                                "Awaiting input",
+                                "customfield_100",
+                            )
+                        ],
                     ),
                     Change(
                         "2018-01-10 10:01:01",
diff --git a/jira_agile_metrics/calculators/progressreport_test.py b/jira_agile_metrics/calculators/progressreport_test.py
index df04f9e..49e8be6 100644
--- a/jira_agile_metrics/calculators/progressreport_test.py
+++ b/jira_agile_metrics/calculators/progressreport_test.py
@@ -280,7 +280,14 @@ def simple_ql(i, jql):
                     changes=[
                         Change(
                             "2018-01-02 10:01:01",
-                            [("Flagged", None, "Impediment", "customfield_100")],
+                            [
+                                (
+                                    "Flagged",
+                                    None,
+                                    "Impediment",
+                                    "customfield_100",
+                                )
+                            ],
                         ),
                         Change(
                             "2018-01-03 01:00:00",
@@ -343,7 +350,14 @@ def simple_ql(i, jql):
                         ),
                         Change(
                             "2018-01-04 10:01:01",
-                            [("Flagged", None, "Impediment", "customfield_100")],
+                            [
+                                (
+                                    "Flagged",
+                                    None,
+                                    "Impediment",
+                                    "customfield_100",
+                                )
+                            ],
                         ),  # should clear two days later when issue resolved
                         Change(
                             "2018-01-05 01:01:01",
@@ -409,11 +423,25 @@ def simple_ql(i, jql):
                         ),
                         Change(
                             "2018-01-07 01:01:01",
-                            [("Flagged", None, "Awaiting input", "customfield_100")],
+                            [
+                                (
+                                    "Flagged",
+                                    None,
+                                    "Awaiting input",
+                                    "customfield_100",
+                                )
+                            ],
                         ),
                         Change(
                             "2018-01-10 10:01:01",
-                            [("Flagged", "Awaiting input", "", "customfield_100")],
+                            [
+                                (
+                                    "Flagged",
+                                    "Awaiting input",
+                                    "",
+                                    "customfield_100",
+                                )
+                            ],
                         ),  # blocked 3 days
                     ],
                 ),
diff --git a/jira_agile_metrics/conftest.py b/jira_agile_metrics/conftest.py
index dc06a6f..beb5bec 100644
--- a/jira_agile_metrics/conftest.py
+++ b/jira_agile_metrics/conftest.py
@@ -31,6 +31,7 @@ def __init__(self, fields):
 
 class FauxChangeItem(object):
     """An item in a changelog change"""
+
     def __init__(self, field, fromString, toString, fieldId=None):
         self.field = field
         self.fieldId = fieldId if fieldId is not None else field
diff --git a/jira_agile_metrics/querymanager.py b/jira_agile_metrics/querymanager.py
index 61c455d..458b943 100644
--- a/jira_agile_metrics/querymanager.py
+++ b/jira_agile_metrics/querymanager.py
@@ -8,12 +8,14 @@
 
 logger = logging.getLogger(__name__)
 
+
 def _field_id_from_changelog_item(history_item):
-    if hasattr(history_item, 'fieldId'):
+    if hasattr(history_item, "fieldId"):
         return history_item.fieldId
     else:
         return history_item.field
 
+
 class IssueSnapshot(object):
     """A snapshot of the key fields of an issue
     at a point in its change history"""
@@ -188,7 +190,7 @@ def iter_changes(self, issue, fields):
 
             field_id = self.field_name_to_id(field)
             field_ids_to_names[field_id] = field
-            
+
             initial_value = self.resolve_field_value(issue, field_id)
             try:
                 initial_value = next(
@@ -227,7 +229,9 @@ def iter_changes(self, issue, fields):
             for item in change.items:
                 if _field_id_from_changelog_item(item) in field_ids_to_names:
                     yield IssueSnapshot(
-                        change=field_ids_to_names[_field_id_from_changelog_item(item)],
+                        change=field_ids_to_names[
+                            _field_id_from_changelog_item(item)
+                        ],
                         key=issue.key,
                         date=change_date,
                         from_string=item.fromString,
diff --git a/pyproject.toml b/pyproject.toml
index 920b075..5715654 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -1,5 +1,5 @@
 [tool.black]
-line-length = 179
+line-length = 79
 include = '\.pyi?$'
 exclude = '''
 /(