diff --git a/lib/Internal/Insert.hs b/lib/Internal/Insert.hs
index 740d11b..be2838c 100644
--- a/lib/Internal/Insert.hs
+++ b/lib/Internal/Insert.hs
@@ -323,7 +323,7 @@ insertIncome
             tax =
               allocateTax precision gross preDeductions scaler $
                 flatTax ++ concatMap (selectAllos day) intTax
-            aftertaxGross = sumAllos $ tax ++ pre
+            aftertaxGross = gross - sumAllos (tax ++ pre)
             post =
               allocatePost precision aftertaxGross $
                 flatPost ++ concatMap (selectAllos day) intPost