diff --git a/README.ja.md b/README.ja.md
index 81d7178e..9c73c0b2 100644
--- a/README.ja.md
+++ b/README.ja.md
@@ -1176,7 +1176,8 @@ report:
                 [-debug-sql]
                 [-pipe]
 
-                [SERVER]...
+		[RFC3339 datetime format under results dir]
+
   -aws-profile string
         AWS profile to use (default "default")
   -aws-region string
diff --git a/README.md b/README.md
index 7c40a6f7..e3bc0eb2 100644
--- a/README.md
+++ b/README.md
@@ -1187,7 +1187,8 @@ report:
                 [-debug-sql]
                 [-pipe]
 
-                [SERVER]...
+		[RFC3339 datetime format under results dir]
+
   -aws-profile string
         AWS profile to use (default "default")
   -aws-region string
diff --git a/commands/report.go b/commands/report.go
index 1542347d..1e69b32e 100644
--- a/commands/report.go
+++ b/commands/report.go
@@ -131,7 +131,7 @@ func (*ReportCmd) Usage() string {
 		[-debug-sql]
 		[-pipe]
 
-		[SERVER]...
+		[RFC3339 datetime format under results dir]
 `
 }