--- main/sc/source/ui/unoobj/chart2uno.cxx
+++ main/sc/source/ui/unoobj/chart2uno.cxx
@@ -3026,31 +3026,38 @@ uno::Sequence< double > SAL_CALL ScChart2DataSequence::getNumericalData()
         }
         else
         {
-            sal_Int32 nMax = 0, nMin = 0, nMaxStep = 0, nMinStep = 0;
-            for (sal_Int32 j = 0; j < nStep; j++)
+            double fMaxVal = fNAN, fMinVal = fNAN;
+            int nMaxStep = -1, nMinStep = -1;
+            for( sal_Int32 j = 0; j < nStep; ++j, ++itr)
             {
-                sal_Int32 nValue = itr->mbIsValue ? itr->mfValue : fNAN;
-                if (nValue > nMax)
+                if( !itr->mbIsValue )
+                    continue;
+                const double fValue = itr->mfValue;
+                if( nMaxStep < 0 )
+                {
+                    nMaxStep = nMinStep = j;
+                    fMaxVal = fMinVal = fValue;
+                }
+                else if( fMaxVal < fValue )
                 {
-                    nMax = nValue;
+                    fMaxVal = fValue;
                     nMaxStep = j;
                 }
-                if (nValue < nMin)
+                else if( fMinVal > fValue )
                 {
-                    nMin = nValue;
+                    fMinVal = fValue;
                     nMinStep = j;
                 }
-                itr++;
             }
             if (nMaxStep > nMinStep)
             {
-                *pArr++ = nMin;
-                *pArr++ = nMax;
+                *(pArr++) = fMinVal;
+                *(pArr++) = fMaxVal;
             }
             else
             {
-                *pArr++ = nMax;
-                *pArr++ = nMin;
+                *(pArr++) = fMaxVal;
+                *(pArr++) = fMinVal;
             }
         }
     }