diff --git a/README.md b/README.md
index bd7076b..268db97 100644
--- a/README.md
+++ b/README.md
@@ -60,7 +60,9 @@ Note that `req` is a [Rack::Request](http://rack.rubyforge.org/doc/classes/Rack/
 
     # Throttle requests to 5 requests per second per ip
     Rack::Attack.throttle('req/ip', :limit => 5, :period => 1.second) do |req|
-      # If the return value is truthy, the cache key for "rack::attack:req/ip:#{req.ip}" is incremented and checked.
+      # If the return value is truthy, the cache key for
+      # "rack::attack:#{Time.now.to_i/1.second}:req/ip:#{req.ip}"
+      # is incremented and compared with the limit.
       # If falsy, the cache key is neither incremented or checked.
       req.ip
     end
@@ -100,6 +102,11 @@ Similarly for blacklisted responses:
       [ 503, {}, ['Blocked']]
     end
 
+For responses that did not exceed a throttle limit, Rack::Attack annotates the environment with match data.
+For example, in out `reqs/ip` throttle above, a matching request would have:
+
+    request.env['rack.attack.throttle_data']['req/ip'] # => { :period => 1, :limit => 5, :count => n }
+
 ## Logging & Instrumentation
 
 Rack::Attack uses the [ActiveSupport::Notifications](http://api.rubyonrails.org/classes/ActiveSupport/Notifications.html) API if available.