diff --git a/lib/CurlRequest.php b/lib/CurlRequest.php
index 648296d..b4517e4 100644
--- a/lib/CurlRequest.php
+++ b/lib/CurlRequest.php
@@ -35,6 +35,13 @@ class CurlRequest
      */
     public static $lastHttpResponseHeaders = array();
 
+    /**
+     * Total time spent in sleep during multiple requests (in seconds)
+     *
+     * @var int
+     */
+    public static $totalRetrySleepTime = 0;
+
     /**
      * Curl additional configuration
      *
@@ -196,6 +203,7 @@ protected static function processRequest($ch)
                 break;
             }
 
+            self::$totalRetrySleepTime += (float)$retryAfter;
             sleep((float)$retryAfter);
         }
 
@@ -210,5 +218,4 @@ protected static function processRequest($ch)
 
         return $response->getBody();
     }
-
 }