diff --git a/requirements.txt b/requirements.txt
index 6891035..4def03e 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -6,5 +6,5 @@ pytest-doctestplus==0.3.0
 pytest-openfiles==0.3.2
 pytest-remotedata==0.3.1
 python-dateutil==2.8.0
-PyYAML==5.1.1
+PyYAML==5.4
 matplotlib==3.1.1