diff --git a/checksum.py b/checksum.py
index 7ba5d19..7f3d6a7 100644
--- a/checksum.py
+++ b/checksum.py
@@ -5,7 +5,9 @@ with open(sys.argv[1], mode='rb') as file:
 	file.read(4) # discard first four bytes
 	rombin = file.read() # read rest of file
 	cksum = 0
+	count = 0;
 	for i in struct.unpack('>' + str(len(rombin)/2) + 'H', rombin):
-		cksum += i;
+		cksum += i
+		count += 1
 	cksum &= 0xFFFFFFFF
 	print(hex(cksum))