diff --git a/src/templates/ja/2019/base.html b/src/templates/ja/2019/base.html
index 8cac6fdce7f..13c4d65446e 100644
--- a/src/templates/ja/2019/base.html
+++ b/src/templates/ja/2019/base.html
@@ -5,7 +5,7 @@
 {% block twitter_image_alt %}{{ year }} Web Almanac{% endblock %}
 
 {% block date_published %}2019-11-04T12:00:00.000Z{% endblock %}
-{% block date_modified %}2020-05-14T00:00:00.000Z{% endblock %}
+{% block date_modified %}2020-05-16T00:00:00.000Z{% endblock %}
 
 {% block breadcrumb_name_1 %}{{ year }} ホーム{% endblock %}
 {% block breadcrumb_name_2 %}{% endblock %}
diff --git a/src/templates/ja/2019/base_ebook.html b/src/templates/ja/2019/base_ebook.html
index 6ba29f8cdc4..694f41c5457 100644
--- a/src/templates/ja/2019/base_ebook.html
+++ b/src/templates/ja/2019/base_ebook.html
@@ -3,7 +3,7 @@
 {% block title %}{{ year }} HTTP ArchiveによるWeb Almanac{% endblock %}
 
 {% block date_published %}2020-05-10T12:00:00.000Z{% endblock %}
-{% block date_modified %}2020-05-14T00:00:00.000Z{% endblock %}
+{% block date_modified %}2020-05-16T00:00:00.000Z{% endblock %}
 
 {% block intro_title %}{{ year }} Web Almanac{% endblock %}
 {% block intro_sub_title %}HTTP Archiveの年次報告書ウェブの状態レポート{% endblock %}