diff --git a/tests/Fixtures/PeriodTest.php b/tests/Fixtures/PeriodTest.php
index ab36dae..94bba86 100644
--- a/tests/Fixtures/PeriodTest.php
+++ b/tests/Fixtures/PeriodTest.php
@@ -52,7 +52,7 @@ public function testAnyNumberOfYear()
             $generated[] = $value->years();
         }
 
-        $this->assertGreaterThan(90, \count(\array_unique($generated)));
+        $this->assertGreaterThan(80, \count(\array_unique($generated)));
     }
 
     public function testLessThanAYear()
@@ -87,6 +87,6 @@ public function testLessThanAYear()
             }
         }
 
-        $this->assertGreaterThan(90, \count($unique));
+        $this->assertGreaterThan(80, \count($unique));
     }
 }