diff --git a/core/src/main/java/com/yahoo/ycsb/measurements/OneMeasurementHistogram.java b/core/src/main/java/com/yahoo/ycsb/measurements/OneMeasurementHistogram.java
index 4e8f5642..a929fec8 100644
--- a/core/src/main/java/com/yahoo/ycsb/measurements/OneMeasurementHistogram.java
+++ b/core/src/main/java/com/yahoo/ycsb/measurements/OneMeasurementHistogram.java
@@ -1,200 +1,200 @@
 /**                                                                                                                                                                                
  * Copyright (c) 2010 Yahoo! Inc. All rights reserved.                                                                                                                             
  *                                                                                                                                                                                 
  * Licensed under the Apache License, Version 2.0 (the "License"); you                                                                                                             
  * may not use this file except in compliance with the License. You                                                                                                                
  * may obtain a copy of the License at                                                                                                                                             
  *                                                                                                                                                                                 
  * http://www.apache.org/licenses/LICENSE-2.0                                                                                                                                      
  *                                                                                                                                                                                 
  * Unless required by applicable law or agreed to in writing, software                                                                                                             
  * distributed under the License is distributed on an "AS IS" BASIS,                                                                                                               
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or                                                                                                                 
  * implied. See the License for the specific language governing                                                                                                                    
  * permissions and limitations under the License. See accompanying                                                                                                                 
  * LICENSE file.                                                                                                                                                                   
  */
 
 package com.yahoo.ycsb.measurements;
 
 import java.io.IOException;
 import java.text.DecimalFormat;
 import java.util.HashMap;
 import java.util.Properties;
 
 import com.yahoo.ycsb.measurements.exporter.MeasurementsExporter;
 
 
 /**
  * Take measurements and maintain a histogram of a given metric, such as READ LATENCY.
  * 
  * @author cooperb
  *
  */
 public class OneMeasurementHistogram extends OneMeasurement
 {
 	public static final String BUCKETS="histogram.buckets";
 	public static final String BUCKETS_DEFAULT="1000";
 
 
 	/**
 	 * Specify the range of latencies to track in the histogram.
 	 */
 	int _buckets;
 
 	/**
      * Groups operations in discrete blocks of 1ms width.
      */
 	int[] histogram;
 	
 	/**
 	 * Counts all operations outside the histogram's range.
 	 */
 	int histogramoverflow;
 	
 	/**
 	 * The total number of reported operations.
 	 */
 	int operations;
 	
 	/**
 	 * The sum of each latency measurement over all operations.
 	 * Calculated in ms.
 	 */
-	double totallatency;
+	long totallatency;
 	
 	/**
 	 * The sum of each latency measurement squared over all operations. 
 	 * Used to calculate variance of latency.
 	 * Calculated in ms. 
 	 */
 	double totalsquaredlatency;
 	
 	//keep a windowed version of these stats for printing status
 	int windowoperations;
 	long windowtotallatency;
 	
 	int min;
 	int max;
 	HashMap<Integer,int[]> returncodes;
 
 	public OneMeasurementHistogram(String name, Properties props)
 	{
 		super(name);
 		_buckets=Integer.parseInt(props.getProperty(BUCKETS, BUCKETS_DEFAULT));
 		histogram=new int[_buckets];
 		histogramoverflow=0;
 		operations=0;
 		totallatency=0;
 		totalsquaredlatency=0;
 		windowoperations=0;
 		windowtotallatency=0;
 		min=-1;
 		max=-1;
 		returncodes=new HashMap<Integer,int[]>();
 	}
 
 	/* (non-Javadoc)
 	 * @see com.yahoo.ycsb.OneMeasurement#reportReturnCode(int)
 	 */
 	public synchronized void reportReturnCode(int code)
 	{
 		Integer Icode=code;
 		if (!returncodes.containsKey(Icode))
 		{
 			int[] val=new int[1];
 			val[0]=0;
 			returncodes.put(Icode,val);
 		}
 		returncodes.get(Icode)[0]++;
 	}
 
 
 	/* (non-Javadoc)
 	 * @see com.yahoo.ycsb.OneMeasurement#measure(int)
 	 */
 	public synchronized void measure(int latency)
 	{
 	    //latency reported in us and collected in bucket by ms.
 		if (latency/1000>=_buckets)
 		{
 			histogramoverflow++;
 		}
 		else
 		{
 			histogram[latency/1000]++;
 		}
 		operations++;
-		totallatency += ((double)latency) / 1000;
+		totallatency += latency/1000;
 		totalsquaredlatency += ((double)latency) * ((double)latency) / 1000000;
 		windowoperations++;
 		windowtotallatency += latency;
 		
 		if ( (min<0) || (latency<min) )
 		{
 			min=latency;
 		}
 
 		if ( (max<0) || (latency>max) )
 		{
 			max=latency;
 		}
 	}
 
 
   @Override
   public void exportMeasurements(MeasurementsExporter exporter) 
           throws IOException
   {
     double mean = totallatency/((double)operations);
     double variance = totalsquaredlatency/((double)operations) - (mean * mean);
     exporter.write(getName(), "Operations", operations);
     exporter.write(getName(), "AverageLatency(ms)", mean);
     exporter.write(getName(), "LatencyVariance(ms)", variance);
     exporter.write(getName(), "MinLatency(us)", min);
     exporter.write(getName(), "MaxLatency(us)", max);
     
     int opcounter=0;
     boolean done95th=false;
     for (int i=0; i<_buckets; i++)
     {
       opcounter+=histogram[i];
       if ( (!done95th) && (((double)opcounter)/((double)operations)>=0.95) )
       {
         exporter.write(getName(), "95thPercentileLatency(ms)", i);
         done95th=true;
       }
       if (((double)opcounter)/((double)operations)>=0.99)
       {
         exporter.write(getName(), "99thPercentileLatency(ms)", i);
         break;
       }
     }
 
     for (Integer I : returncodes.keySet())
     {
       int[] val=returncodes.get(I);
       exporter.write(getName(), "Return="+I, val[0]);
     }     
 
     for (int i=0; i<_buckets; i++)
     {
       exporter.write(getName(), Integer.toString(i), histogram[i]);
     }
     exporter.write(getName(), ">"+_buckets, histogramoverflow);
   }
 
 	@Override
 	public String getSummary() {
 		if (windowoperations==0)
 		{
 			return "";
 		}
 		DecimalFormat d = new DecimalFormat("#.##");
 		double report=((double)windowtotallatency)/((double)windowoperations);
 		windowtotallatency=0;
 		windowoperations=0;
 		return "["+getName()+" AverageLatency(us)="+d.format(report)+"]";
 	}
 
 }