diff --git a/spreadsheets/README.md b/spreadsheets/README.md
new file mode 100644
index 0000000..5996ceb
--- /dev/null
+++ b/spreadsheets/README.md
@@ -0,0 +1,6 @@
+# Spreadsheets
+
+These spreadsheets were created and edited with the LibreOffice program.
+
+It is uncertain if these files can be opened with MS Excel, so it would be best
+to stick with LibreOffice.