diff --git a/org.ntlab.traceAnalyzer/src/org/ntlab/deltaExtractor/Alias.java b/org.ntlab.traceAnalyzer/src/org/ntlab/deltaExtractor/Alias.java
index 15e6bb8..c59c4c6 100644
--- a/org.ntlab.traceAnalyzer/src/org/ntlab/deltaExtractor/Alias.java
+++ b/org.ntlab.traceAnalyzer/src/org/ntlab/deltaExtractor/Alias.java
@@ -1,5 +1,7 @@
 package org.ntlab.deltaExtractor;
+import org.ntlab.deltaExtractor.Alias.AliasType;
 import org.ntlab.trace.MethodExecution;
+import org.ntlab.trace.MethodInvocation;
 import org.ntlab.trace.Statement;
 import org.ntlab.trace.TracePoint;
 /**
@@ -63,7 +65,27 @@
 	public String getMethodSignature() {
 		return occurrencePoint.getMethodExecution().getSignature();
 	}
-	
+
+	/**
+	 * Get time stamp of statement.
+	 * @return
+	 */
+	public long getTimeStamp() {
+		if (!occurrencePoint.isValid()) {
+			return occurrencePoint.getMethodExecution().getEntryTime();
+		}
+		long stTimeStamp = occurrencePoint.getStatement().getTimeStamp();
+		Statement st = occurrencePoint.getStatement();
+		if (aliasType == AliasType.RETURN_VALUE) {
+			stTimeStamp = occurrencePoint.getMethodExecution().getExitTime();
+		} else if (aliasType == AliasType.METHOD_INVOCATION && st instanceof MethodInvocation) {
+			stTimeStamp = ((MethodInvocation) st).getCalledMethodExecution().getExitTime();
+		} else if (aliasType == AliasType.FORMAL_PARAMETER) {
+			stTimeStamp = occurrencePoint.getMethodExecution().getEntryTime();			
+		}
+		return stTimeStamp;
+	}
+
 	public int getLineNo() {
 		try {
 			Statement statement = occurrencePoint.getStatement();