diff --git a/src/Qwack.Core/Instruments/Cashflow.cs b/src/Qwack.Core/Instruments/Cashflow.cs
index e0dd1a59..24b5c407 100644
--- a/src/Qwack.Core/Instruments/Cashflow.cs
+++ b/src/Qwack.Core/Instruments/Cashflow.cs
@@ -102,7 +102,7 @@ public CashFlow(TO_Cashflow to, ICalendarProvider calendarProvider, ICurrencyPro
             FixedRateOrMargin = FixedRateOrMargin,
             FlowType = FlowType,
             Basis = Basis,
-            RateIndex = RateIndex.GetTransportObject(),
+            RateIndex = RateIndex?.GetTransportObject(),
             Dcf = Dcf,
             CpiFixingLagInMonths = CpiFixingLagInMonths,
             AssetId = AssetId,
diff --git a/version.props b/version.props
index f7a98e02..58984f4a 100644
--- a/version.props
+++ b/version.props
@@ -1,5 +1,5 @@
 <Project>
     <PropertyGroup>
-        <VersionPrefix>0.7.39</VersionPrefix>
+        <VersionPrefix>0.7.40</VersionPrefix>
     </PropertyGroup>
 </Project>
diff --git a/version.txt b/version.txt
index 18296cbe..0be87394 100644
--- a/version.txt
+++ b/version.txt
@@ -1 +1 @@
-0.7.39
\ No newline at end of file
+0.7.40
\ No newline at end of file