diff --git a/Gemfile b/Gemfile
index d4bd2cb..9eced70 100644
--- a/Gemfile
+++ b/Gemfile
@@ -5,7 +5,7 @@ gem 'coderay', '~> 1.1.0'
 gem 'rake-jekyll', '~> 1.1.0'
 gem 'csv', '~> 3.3.5'
 gem 'base64', '~> 0.3.0'
- gem 'bigdecimal', '~> 3.1'
+ gem 'bigdecimal', '~> 4.0'
 
 group :jekyll_plugins do
   gem 'jekyll-asciidoc', '~> 3.0.0'