diff --git a/src/main/java/org/apache/datasketches/kll/KllFloatsSketchSortedView.java b/src/main/java/org/apache/datasketches/kll/KllFloatsSketchSortedView.java
index fc64c0d..52320dd 100644
--- a/src/main/java/org/apache/datasketches/kll/KllFloatsSketchSortedView.java
+++ b/src/main/java/org/apache/datasketches/kll/KllFloatsSketchSortedView.java
@@ -104,6 +104,11 @@
   }
 
   @Override
+  public int getNumRetained() {
+    return quantiles.length;
+  }
+
+  @Override
   public float getQuantile(final double rank, final QuantileSearchCriteria searchCrit) {
     if (isEmpty()) { throw new SketchesArgumentException(EMPTY_MSG); }
     QuantilesUtil.checkNormalizedRankBounds(rank);
diff --git a/src/main/java/org/apache/datasketches/quantilescommon/DoublesSketchSortedView.java b/src/main/java/org/apache/datasketches/quantilescommon/DoublesSketchSortedView.java
index b033236..8930085 100644
--- a/src/main/java/org/apache/datasketches/quantilescommon/DoublesSketchSortedView.java
+++ b/src/main/java/org/apache/datasketches/quantilescommon/DoublesSketchSortedView.java
@@ -75,6 +75,11 @@
   }
 
   @Override
+  public int getNumRetained() {
+    return quantiles.length;
+  }
+
+  @Override
   public double getQuantile(final double rank, final QuantileSearchCriteria searchCrit) {
     if (isEmpty()) { throw new SketchesArgumentException(EMPTY_MSG); }
     QuantilesUtil.checkNormalizedRankBounds(rank);
diff --git a/src/main/java/org/apache/datasketches/quantilescommon/ItemsSketchSortedView.java b/src/main/java/org/apache/datasketches/quantilescommon/ItemsSketchSortedView.java
index e3228e3..db0a612 100644
--- a/src/main/java/org/apache/datasketches/quantilescommon/ItemsSketchSortedView.java
+++ b/src/main/java/org/apache/datasketches/quantilescommon/ItemsSketchSortedView.java
@@ -46,7 +46,7 @@
   private final T maxItem;
   private final T minItem;
   private final Class<T> clazz;
-  private final double normRankErr;
+  private final double normRankErr;//assumes PMF type error
 
   /**
    * Construct from elements, also used in testing.
@@ -113,6 +113,11 @@
   }
 
   @Override
+  public int getNumRetained() {
+    return quantiles.length;
+  }
+
+  @Override
   @SuppressWarnings("unchecked")
   public GenericPartitionBoundaries<T> getPartitionBoundaries(final int numEquallySized,
       final QuantileSearchCriteria searchCrit) {
diff --git a/src/main/java/org/apache/datasketches/quantilescommon/SortedView.java b/src/main/java/org/apache/datasketches/quantilescommon/SortedView.java
index 5fb5029..9380355 100644
--- a/src/main/java/org/apache/datasketches/quantilescommon/SortedView.java
+++ b/src/main/java/org/apache/datasketches/quantilescommon/SortedView.java
@@ -49,6 +49,12 @@
   long getN();
 
   /**
+   * Gets the number of quantiles retained by the sketch.
+   * @return the number of quantiles retained by the sketch
+   */
+  int getNumRetained();
+
+  /**
    * Returns true if this sorted view is empty.
    * @return true if this sorted view is empty.
    */
diff --git a/src/main/java/org/apache/datasketches/req/ReqSketchSortedView.java b/src/main/java/org/apache/datasketches/req/ReqSketchSortedView.java
index 4084222..7f97a43 100644
--- a/src/main/java/org/apache/datasketches/req/ReqSketchSortedView.java
+++ b/src/main/java/org/apache/datasketches/req/ReqSketchSortedView.java
@@ -95,6 +95,11 @@
   }
 
   @Override
+  public int getNumRetained() {
+    return quantiles.length;
+  }
+
+  @Override
   public float getQuantile(final double rank, final QuantileSearchCriteria searchCrit) {
     if (isEmpty()) { throw new IllegalArgumentException(QuantilesAPI.EMPTY_MSG); }
     QuantilesUtil.checkNormalizedRankBounds(rank);