All values ​​"Entry.getVal ()" equal
diff --git a/MPChartLib/src/com/github/mikephil/charting/data/ChartData.java b/MPChartLib/src/com/github/mikephil/charting/data/ChartData.java
index 9988230..81c7244 100644
--- a/MPChartLib/src/com/github/mikephil/charting/data/ChartData.java
+++ b/MPChartLib/src/com/github/mikephil/charting/data/ChartData.java
@@ -183,6 +183,11 @@
         if (mYMax < entry.getVal()) {
             mYMax = entry.getVal();
         }
+
+        if (mYMin == mYMax) {
+            mYMin--;
+            mYMax++;
+        }
     }
 
     public int getDataSetCount() {