diff --git a/code/GoogleSitemapDecorator.php b/code/GoogleSitemapDecorator.php
index 4e85382..9867bc0 100644
--- a/code/GoogleSitemapDecorator.php
+++ b/code/GoogleSitemapDecorator.php
@@ -81,7 +81,7 @@ class GoogleSitemapSiteTreeDecorator extends SiteTreeDecorator {
 			return max(0.1, 1.0 - ($numParents / 10));
 		} 
 		elseif ($this->owner->getField('Priority') == -1) {
-			return 0;
+			return -1;
 		} 
 		else {
 			$priority = abs($this->owner->getField('Priority'));
@@ -129,4 +129,4 @@ class GoogleSitemapSiteTreeDecorator extends SiteTreeDecorator {
 			$this->owner->ChangeFreq = 'always';
 		}
 	}
-}
\ No newline at end of file
+}