diff --git a/lib/core/settings.py b/lib/core/settings.py
index 16177db67..59f94649d 100644
--- a/lib/core/settings.py
+++ b/lib/core/settings.py
@@ -67,6 +67,10 @@ INFERENCE_BLANK_BREAK = 10
 # string used for representation of unknown dbms version
 UNKNOWN_DBMS_VERSION = "Unknown"
 
+# lower and upper values for match ratio in case of stable page
+LOWER_RATIO_BOUND = 0.02
+UPPER_RATIO_BOUND = 0.98
+
 # System variables
 IS_WIN             = subprocess.mswindows
 # The name of the operating system dependent module imported. The following
diff --git a/lib/request/comparison.py b/lib/request/comparison.py
index 40c158060..392cb5bf0 100644
--- a/lib/request/comparison.py
+++ b/lib/request/comparison.py
@@ -18,6 +18,7 @@ from lib.core.data import kb
 from lib.core.data import logger
 from lib.core.settings import CONSTANT_RATIO
 from lib.core.settings import DIFF_TOLERANCE
+from lib.core.settings import LOWER_RATIO_BOUND, UPPER_RATIO_BOUND
 
 def comparison(page, headers=None, getSeqMatcher=False, pageLength=None):
     if page is None and pageLength is None:
@@ -93,11 +94,11 @@ def comparison(page, headers=None, getSeqMatcher=False, pageLength=None):
         if conf.thold:
             kb.matchRatio = conf.thold
 
-        elif kb.pageStable and ratio > 0.6 and ratio < 0.99:
+        elif kb.pageStable and ratio >= LOWER_RATIO_BOUND and ratio <= UPPER_RATIO_BOUND:
             kb.matchRatio = ratio
             logger.debug("setting match ratio for current parameter to %.3f" % kb.matchRatio)
 
-        elif not kb.pageStable or ( kb.pageStable and ratio < 0.6 ):
+        elif not kb.pageStable:
             kb.matchRatio = CONSTANT_RATIO
             logger.debug("setting match ratio for current parameter to default value 0.900")