diff --git a/R/data.R b/R/data.R
index fd32cc4c..4bbd16a2 100644
--- a/R/data.R
+++ b/R/data.R
@@ -1,4 +1,4 @@
-# Copyright (C) 2021-2023 Hibiki AI Limited <info@hibiki-ai.com>
+# Copyright (C) 2021-2024 Hibiki AI Limited <info@hibiki-ai.com>
 #
 # This file is part of ichimoku.
 #
@@ -38,7 +38,7 @@
 
 .__global__ <- ".data"
 
-.user_agent <- sprintf("r-ichimoku/%s", as.character(packageVersion("ichimoku")))
+.user_agent <- strcat("r-ichimoku/", as.character(packageVersion("ichimoku")))
 
 .mlgrid_pairs <- {
   cols <- c("chikou", "close", "high", "low", "tenkan", "kijun", "senkouA", "senkouB", "cloudT", "cloudB")
diff --git a/R/oanda.R b/R/oanda.R
index df66c719..f0491d01 100644
--- a/R/oanda.R
+++ b/R/oanda.R
@@ -1,4 +1,4 @@
-# Copyright (C) 2021-2023 Hibiki AI Limited <info@hibiki-ai.com>
+# Copyright (C) 2021-2024 Hibiki AI Limited <info@hibiki-ai.com>
 #
 # This file is part of ichimoku.
 #
diff --git a/inst/CITATION b/inst/CITATION
index 4e6e30c5..46442b24 100644
--- a/inst/CITATION
+++ b/inst/CITATION
@@ -1,6 +1,6 @@
 bibentry(bibtype = "Manual",
          title = "ichimoku: Visualization and Tools for Ichimoku Kinko Hyo Strategies",
          author = person("Charlie", "Gao"),
-         year = 2023,
+         year = 2024,
          note = sprintf("R package version %s", meta$Version),
          url = "https://doi.org/10.5281/zenodo.7879346")