diff --git a/src/MainSequence.cpp b/src/MainSequence.cpp
index 45b417808..4f73b506e 100644
--- a/src/MainSequence.cpp
+++ b/src/MainSequence.cpp
@@ -804,15 +804,15 @@ DBL_DBL MainSequence::CalculateMainSequenceCoreMassShikauchi(const double p_Dt,
             double deltaYout = f1 / f2 * deltaCoreMass;
 
             // Calculate the change in core helium abundance, assuming linear profile between Yc and Y0, and that the the accreted gas has helium fraction Y0
-            double deltaY            = (m_HeliumAbundanceCoreOut - m_HeliumAbundanceCore) / f3 * deltaCoreMass + 0.5 / f3 * f1 / f2 * deltaCoreMass * deltaCoreMass;
-            newCentralHeliumFraction = m_HeliumAbundanceCore + deltaY;
-            m_HeliumAbundanceCoreOut  += deltaYout;
+            double deltaY             = (m_HeliumAbundanceCoreOut - m_HeliumAbundanceCore) / f3 * deltaCoreMass + 0.5 / f3 * f1 / f2 * deltaCoreMass * deltaCoreMass;
+            newCentralHeliumFraction  = m_HeliumAbundanceCore + deltaY;
+            m_HeliumAbundanceCoreOut += deltaYout;
         }
         else {                                                                                                                                                  // New core mass greater or equal to the initial core mass?
             double deltaCoreMass1         = m_InitialMainSequenceCoreMass - m_MainSequenceCoreMass;                                                             // Mass accreted up to the initial core mass
             double deltaCoreMass2         = deltaCoreMass - deltaCoreMass1;                                                                                     // Remaining accreted mass
             newCentralHeliumFraction      = (m_MainSequenceCoreMass * m_HeliumAbundanceCore + 0.5 * (m_HeliumAbundanceCoreOut + m_InitialHeliumAbundance) * deltaCoreMass1 + deltaCoreMass2 * m_InitialHeliumAbundance) / (m_MainSequenceCoreMass + deltaCoreMass);
-            m_HeliumAbundanceCoreOut        = m_InitialHeliumAbundance;
+            m_HeliumAbundanceCoreOut      = m_InitialHeliumAbundance;
             m_InitialMainSequenceCoreMass = newMixingCoreMass;
         }
     }
diff --git a/src/MainSequence.h b/src/MainSequence.h
index 8c95b5d99..c035345e5 100644
--- a/src/MainSequence.h
+++ b/src/MainSequence.h
@@ -26,7 +26,7 @@ class MainSequence: virtual public BaseStar {
     
     // member variables
     
-    double          m_HeliumAbundanceCoreOut = m_InitialHeliumAbundance;                                                                                            // Helium abundance just outside the core, used for rejuvenation calculations
+    double          m_HeliumAbundanceCoreOut      = m_InitialHeliumAbundance;                                                                                       // Helium abundance just outside the core, used for rejuvenation calculations
     double          m_InitialMainSequenceCoreMass = 0.0;                                                                                                            // Initial mass of the mixing core is initialised in MS_gt_07 class
 
     // member functions - alphabetically