diff --git a/views.py b/views.py
index ecb744a..f8c7ecb 100644
--- a/views.py
+++ b/views.py
@@ -345,6 +345,22 @@ class UpperLimitView(APIView):
 
             Flux = max(FL, 0)  # flux cannot be lower than zero
 
+            # NORMALIZED BACKGROUND RATE
+            # ****************************************************************
+            # in units of ct/s/keV/arcmin^2
+
+            sr_to_arcmin2 = (180 / np.pi * 60) ** 2
+
+            pix_area = (
+                hp.nside2pixarea(nside=4096) * sr_to_arcmin2
+            )  # nside2pixarea yields area in sr
+
+            bg_area = pix_area * Bnpix  # get total bg region area
+
+            en_range = 12 - 4
+
+            NBR = Bcounts / t / en_range / bg_area
+
         # handle exceptions: write error text to the response
         # zero out all math results
         except Exception as e:
@@ -531,6 +547,7 @@ class UpperLimitView(APIView):
             # count rates
             "SourceRate": CR,
             "BackgroundRate": BR,
+            "NormalizedBackgroundRate": NBR,  # ct/s/keV/arcmin2
             # contamination
             "Contamination": contamination,
             "NearbySources": nearby_sources,