diff --git a/rowers/dataprep.py b/rowers/dataprep.py
index b7043a7f..e055f8ef 100644
--- a/rowers/dataprep.py
+++ b/rowers/dataprep.py
@@ -553,7 +553,10 @@ def setcp(workout, background=False, recurrance=True):
             # check dts
             tarr = datautils.getlogarr(4000)
             if df['delta'][0] in tarr:
-                return(df, df['delta'], df['cp'])
+                try:
+                    return(df, df['delta'], df['cp'], df['cr'])
+                except KeyError:
+                    return(df, df['delta'], df['cp'], 0*df['cp'])
     except Exception as e:
         try:
             os.remove(filename)
@@ -565,7 +568,7 @@ def setcp(workout, background=False, recurrance=True):
     strokesdf = remove_nulls_pl(strokesdf)
 
     if strokesdf.is_empty():
-        return pl.DataFrame({'delta': [], 'cp': []}), pl.Series(dtype=pl.Float64), pl.Series(dtype=pl.Float64)
+        return pl.DataFrame({'delta': [], 'cp': [], 'cr': []}), pl.Series(dtype=pl.Float64), pl.Series(dtype=pl.Float64), pl.Series(dtype=pl.Float64)
     
     totaltime = strokesdf['time'].max()
     maxt = totaltime/1000.
@@ -580,7 +583,7 @@ def setcp(workout, background=False, recurrance=True):
     elif os.path.exists(csvfilename+'.gz'):  # pragma: no cover
         csvfile = csvfilename+'.gz'
     else:  # pragma: no cover
-        return pl.DataFrame({'delta': [], 'cp': []}), pl.Series(dtype=pl.Float64), pl.Series(dtype=pl.Float64)
+        return pl.DataFrame({'delta': [], 'cp': [], 'cr': []}), pl.Series(dtype=pl.Float64), pl.Series(dtype=pl.Float64), pl.Series(dtype=pl.Float64)
     csvfile = os.path.abspath(csvfile)
 
     with grpc.insecure_channel(
@@ -593,7 +596,7 @@ def setcp(workout, background=False, recurrance=True):
             grpc.channel_ready_future(channel).result(timeout=10)
         except grpc.FutureTimeoutError:  # pragma: no cover
             dologging('metrics.log','grpc channel time out in setcp')
-            return pl.DataFrame({'delta': [], 'cp': []}), pl.Series(dtype=pl.Float64), pl.Series(dtype=pl.Float64)
+            return pl.DataFrame({'delta': [], 'cp': [], 'cr':[]}), pl.Series(dtype=pl.Float64), pl.Series(dtype=pl.Float64), pl.Series(dtype=pl.Float64)
 
         stub = metrics_pb2_grpc.MetricsStub(channel)
         req = metrics_pb2.CPRequest(filename = csvfile, filetype = "CSV", tarr = logarr)
@@ -602,16 +605,18 @@ def setcp(workout, background=False, recurrance=True):
             response = stub.GetCP(req, timeout=60)
         except Exception as e:
             dologging('metrics.log', traceback.format_exc())
-            return pl.DataFrame({'delta': [], 'cp': []}), pl.Series(dtype=pl.Float64), pl.Series(dtype=pl.Float64)
+            return pl.DataFrame({'delta': [], 'cp': [], 'cr': []}), pl.Series(dtype=pl.Float64), pl.Series(dtype=pl.Float64), pl.Series(dtype=pl.Float64)
 
     delta = pl.Series(np.array(response.delta))
     cpvalues = pl.Series(np.array(response.power))
     powermean = response.avgpower
+    spmvalues = pl.Series(np.array(response.spm))
 
     try:
         df = pl.DataFrame({
             'delta': delta,
             'cp': cpvalues,
+            'cr': spmvalues,
             'id': workout.id,
         })
         
@@ -620,7 +625,7 @@ def setcp(workout, background=False, recurrance=True):
 
     except Exception as e:
         dologging("metrics.log", "setcp: "+ str(e))
-        return pl.DataFrame({'delta': [], 'cp': []}), pl.Series(dtype=pl.Float64), pl.Series(dtype=pl.Float64)
+        return pl.DataFrame({'delta': [], 'cp': [], 'cr': []}), pl.Series(dtype=pl.Float64), pl.Series(dtype=pl.Float64), pl.Series(dtype=pl.Float64)
 
     #df.to_parquet(filename, engine='fastparquet', compression='GZIP')
 
@@ -631,7 +636,7 @@ def setcp(workout, background=False, recurrance=True):
         workout.goldmedalduration = goldmedalduration
         workout.save()
 
-    return df, delta, cpvalues
+    return df, delta, cpvalues, spmvalues # pragma: no cover
     
 
 
@@ -772,7 +777,7 @@ def fetchcp_new(rower, workouts):
     data = []
 
     for workout in workouts:
-        df, delta, cpvalues = setcp(workout)
+        df, delta, cpvalues, cpvalues_spm = setcp(workout)
         df = df.drop('id')
         df = df.with_columns((pl.lit(str(workout))).alias("workout"))
         df = df.with_columns((pl.lit(workout.url())).alias("url"))
@@ -780,7 +785,7 @@ def fetchcp_new(rower, workouts):
             data.append(df)
 
     if len(data) == 0:
-        return pl.Series(dtype=pl.Float64), pl.Series(dtype=pl.Float64), 0, pl.Series(dtype=pl.Float64), pl.Series(dtype=pl.Float64)
+        return pl.Series(dtype=pl.Float64), pl.Series(dtype=pl.Float64), pl.Series(dtype=pl.Float64), 0, pl.Series(dtype=pl.Float64), pl.Series(dtype=pl.Float64)
     if len(data) > 1:
         df = pl.concat(data)
 
@@ -791,11 +796,16 @@ def fetchcp_new(rower, workouts):
             pl.all().sort_by('cp').last(),
         ])
     except (KeyError, ColumnNotFoundError):  # pragma: no cover
-        return pl.Series(dtype=pl.Float64), pl.Series(dtype=pl.Float64), 0, pl.Series(dtype=pl.Float64), pl.Series(dtype=pl.Float64)
+        return pl.Series(dtype=pl.Float64), pl.Series(dtype=pl.Float64), pl.Series(dtype=pl.Float64), 0, pl.Series(dtype=pl.Float64), pl.Series(dtype=pl.Float64)
 
     df = df.filter(pl.col("cp")>20)
 
-    return df['delta'], df['cp'], 0, df['workout'], df['url']
+    try:
+        testje = df['cr']
+    except KeyError:
+        return df['delta'], df['cp'], 0*df['cp'], 0, df['workout'], df['url']
+
+    return df['delta'], df['cp'], df['cr'], 0, df['workout'], df['url']
 
 
 
diff --git a/rowers/datautils.py b/rowers/datautils.py
index 0b24d252..2eeac953 100644
--- a/rowers/datautils.py
+++ b/rowers/datautils.py
@@ -84,7 +84,10 @@ def cpfit(powerdf, fraclimit=0.0001, nmax=1000):
     p1 = p0
 
     thesecs = powerdf['Delta'].to_numpy()
-    theavpower = powerdf['CP'].to_numpy()
+    try:
+        theavpower = powerdf['CP'].to_numpy()
+    except:  # pragma: no cover
+        theavpower = powerdf['CR'].to_numpy()
         
 
     if len(thesecs) >= 4:
diff --git a/rowers/forms.py b/rowers/forms.py
index face5583..a6a1c9d7 100644
--- a/rowers/forms.py
+++ b/rowers/forms.py
@@ -1299,6 +1299,7 @@ analysischoices = (
     ('stats', 'Statistics'),
     ('compare', 'Compare'),
     ('cp', 'CP chart'),
+    ('cr', 'CR chart'),
 )
 
 
diff --git a/rowers/interactiveplots.py b/rowers/interactiveplots.py
index 2f0d2a5d..ae3a25ae 100644
--- a/rowers/interactiveplots.py
+++ b/rowers/interactiveplots.py
@@ -1113,6 +1113,75 @@ def interactive_otwcpchart(powerdf, promember=0, rowername="", r=None,
     return [script, div, p1, ratio, message]
 
 
+def interactive_otwcrchart(powerdf, promember=0, rowername="", r=None,
+                           cpfit='data',
+                           title='', type='water'):
+
+    powerdf2 = powerdf.filter((pl.col("Delta") > 0) & (pl.col("CR") > 0))
+
+    # plot tools
+    if (promember == 1):  # pragma: no cover
+        TOOLS = 'save,pan,box_zoom,wheel_zoom,reset,tap,hover,crosshair'
+    else:
+        TOOLS = 'pan,box_zoom,wheel_zoom,reset,tap,hover,crosshair'
+
+    x_axis_type = 'log'
+
+    deltas = powerdf2['Delta'].apply(lambda x: timedeltaconv(x))
+    powerdf2 = powerdf2.with_columns(
+        ftime = deltas.apply(lambda x: strfdelta(x)),
+        Deltaminutes = pl.col("Delta")/60.
+    )
+
+    # there is no Paul's law for OTW
+
+    thesecs = powerdf2['Delta']
+    theavpower = powerdf2['CR']
+
+    p1, fitt, fitpower, ratio = datautils.cpfit(powerdf2)
+    if cpfit == 'automatic' and r is not None:
+        if type == 'water':
+            p1 = [r.r0, r.r1, r.r2, r.r3]
+            ratio = r.cpratio
+        elif type == 'erg':  # pragma: no cover
+            p1 = [r.er0, r.er1, r.er2, r.er3]
+            ratio = r.ecrratio
+
+        def fitfunc(pars, x):
+            return abs(pars[0])/(1+(x/abs(pars[2]))) + abs(pars[1])/(1+(x/abs(pars[3])))
+
+        fitpower = fitfunc(p1, fitt)
+
+    message = ""
+    # if len(fitpower[fitpower<0]) > 0:
+    # message = "CP model fit didn't give correct results"
+
+    deltas = fitt.apply(lambda x: timedeltaconv(x))
+    ftime = niceformat(deltas)
+
+
+
+    fit_data =  pl.DataFrame(dict(
+            CR=fitpower,
+            CRmax=ratio*fitpower,
+            duration=fitt/60.,
+            ftime=ftime,
+        ))
+
+    if not title:
+        title = "Critical StrokeRate for "+rowername
+    
+    chart_dict = {
+        'data': powerdf2.to_dicts(),
+        'fitdata': fit_data.to_dicts(),
+        'title': title,
+    }
+
+    script, div = get_chart("/cr", chart_dict)
+
+    return [script, div, p1, ratio, message]
+
+
 def interactive_agegroup_plot(df, distance=2000, duration=None,
                               sex='male', weightcategory='hwt'):
 
diff --git a/rowers/models.py b/rowers/models.py
index f1451085..ca4d864c 100644
--- a/rowers/models.py
+++ b/rowers/models.py
@@ -1104,6 +1104,18 @@ class Rower(models.Model):
     ep3 = models.FloatField(default=1.0, verbose_name="erg CP p4")
     ecpratio = models.FloatField(default=1.0, verbose_name="erg CP fit ratio")
 
+    r0 = models.FloatField(default=1.0, verbose_name="CR r1")
+    r1 = models.FloatField(default=1.0, verbose_name="CR r2")
+    r2 = models.FloatField(default=1.0, verbose_name="CR r3")
+    r3 = models.FloatField(default=1.0, verbose_name="CR r4")
+    crratio = models.FloatField(default=1.0, verbose_name="CR fit ratio")
+
+    er0 = models.FloatField(default=1.0, verbose_name="erg CR r1")
+    er1 = models.FloatField(default=1.0, verbose_name="erg CR r2")
+    er2 = models.FloatField(default=1.0, verbose_name="erg CR r3")
+    er3 = models.FloatField(default=1.0, verbose_name="erg CR r4")
+    ecpratio = models.FloatField(default=1.0, verbose_name="erg CP fit ratio")
+
     cprange = models.IntegerField(default=42, verbose_name="Range for calculation of breakthrough workouts and fitness (CP)",
                                   choices=cppresets)
 
diff --git a/rowers/rowing_workout_metrics_pb2.py b/rowers/rowing_workout_metrics_pb2.py
index 80b29670..132e63c3 100644
--- a/rowers/rowing_workout_metrics_pb2.py
+++ b/rowers/rowing_workout_metrics_pb2.py
@@ -24,7 +24,7 @@ _sym_db = _symbol_database.Default()
 
 
 
-DESCRIPTOR = _descriptor_pool.Default().AddSerializedFile(b'\n\x1crowing-workout-metrics.proto\x12\x16rowing_workout_metrics\"\x80\x01\n\x15WorkoutMetricsRequest\x12\x10\n\x08\x66ilename\x18\x01 \x01(\t\x12\x0b\n\x03sex\x18\x02 \x01(\t\x12\x0b\n\x03\x66tp\x18\x03 \x01(\x01\x12\r\n\x05hrftp\x18\x04 \x01(\x01\x12\r\n\x05hrmax\x18\x05 \x01(\x01\x12\r\n\x05hrmin\x18\x06 \x01(\x01\x12\x0e\n\x06wpsavg\x18\x07 \x01(\x01\"\x80\x01\n\x16WorkoutMetricsResponse\x12\x0b\n\x03tss\x18\x01 \x01(\x01\x12\r\n\x05normp\x18\x02 \x01(\x01\x12\r\n\x05trimp\x18\x03 \x01(\x01\x12\r\n\x05hrtss\x18\x04 \x01(\x01\x12\r\n\x05normv\x18\x05 \x01(\x01\x12\r\n\x05normw\x18\x06 \x01(\x01\x12\x0e\n\x06spmtss\x18\x07 \x01(\x01\"=\n\tCPRequest\x12\x10\n\x08\x66ilename\x18\x01 \x01(\t\x12\x10\n\x08\x66iletype\x18\x02 \x01(\t\x12\x0c\n\x04tarr\x18\x03 \x03(\x01\"<\n\nCPResponse\x12\r\n\x05\x64\x65lta\x18\x01 \x03(\x01\x12\r\n\x05power\x18\x02 \x03(\x01\x12\x10\n\x08\x61vgpower\x18\x03 \x01(\x01\x32\xc7\x01\n\x07Metrics\x12l\n\x0b\x43\x61lcMetrics\x12-.rowing_workout_metrics.WorkoutMetricsRequest\x1a..rowing_workout_metrics.WorkoutMetricsResponse\x12N\n\x05GetCP\x12!.rowing_workout_metrics.CPRequest\x1a\".rowing_workout_metrics.CPResponseB\x1aZ\x18./rowing-workout-metricsb\x06proto3')
+DESCRIPTOR = _descriptor_pool.Default().AddSerializedFile(b'\n\x1crowing-workout-metrics.proto\x12\x16rowing_workout_metrics\"\x80\x01\n\x15WorkoutMetricsRequest\x12\x10\n\x08\x66ilename\x18\x01 \x01(\t\x12\x0b\n\x03sex\x18\x02 \x01(\t\x12\x0b\n\x03\x66tp\x18\x03 \x01(\x01\x12\r\n\x05hrftp\x18\x04 \x01(\x01\x12\r\n\x05hrmax\x18\x05 \x01(\x01\x12\r\n\x05hrmin\x18\x06 \x01(\x01\x12\x0e\n\x06wpsavg\x18\x07 \x01(\x01\"\x80\x01\n\x16WorkoutMetricsResponse\x12\x0b\n\x03tss\x18\x01 \x01(\x01\x12\r\n\x05normp\x18\x02 \x01(\x01\x12\r\n\x05trimp\x18\x03 \x01(\x01\x12\r\n\x05hrtss\x18\x04 \x01(\x01\x12\r\n\x05normv\x18\x05 \x01(\x01\x12\r\n\x05normw\x18\x06 \x01(\x01\x12\x0e\n\x06spmtss\x18\x07 \x01(\x01\"=\n\tCPRequest\x12\x10\n\x08\x66ilename\x18\x01 \x01(\t\x12\x10\n\x08\x66iletype\x18\x02 \x01(\t\x12\x0c\n\x04tarr\x18\x03 \x03(\x01\"I\n\nCPResponse\x12\r\n\x05\x64\x65lta\x18\x01 \x03(\x01\x12\r\n\x05power\x18\x02 \x03(\x01\x12\x10\n\x08\x61vgpower\x18\x03 \x01(\x01\x12\x0b\n\x03spm\x18\x04 \x03(\x01\x32\xc7\x01\n\x07Metrics\x12l\n\x0b\x43\x61lcMetrics\x12-.rowing_workout_metrics.WorkoutMetricsRequest\x1a..rowing_workout_metrics.WorkoutMetricsResponse\x12N\n\x05GetCP\x12!.rowing_workout_metrics.CPRequest\x1a\".rowing_workout_metrics.CPResponseB\x1aZ\x18./rowing-workout-metricsb\x06proto3')
 
 _globals = globals()
 _builder.BuildMessageAndEnumDescriptors(DESCRIPTOR, _globals)
@@ -39,7 +39,7 @@ if not _descriptor._USE_C_DESCRIPTORS:
   _globals['_CPREQUEST']._serialized_start=318
   _globals['_CPREQUEST']._serialized_end=379
   _globals['_CPRESPONSE']._serialized_start=381
-  _globals['_CPRESPONSE']._serialized_end=441
-  _globals['_METRICS']._serialized_start=444
-  _globals['_METRICS']._serialized_end=643
+  _globals['_CPRESPONSE']._serialized_end=454
+  _globals['_METRICS']._serialized_start=457
+  _globals['_METRICS']._serialized_end=656
 # @@protoc_insertion_point(module_scope)
diff --git a/rowers/templates/otwcr.html b/rowers/templates/otwcr.html
new file mode 100644
index 00000000..f4d7d849
--- /dev/null
+++ b/rowers/templates/otwcr.html
@@ -0,0 +1,20 @@
+
+  {{ the_div|safe }}
+  <p>
+    <table width="100%" class="listtable">
+      <thead>
+        <tr>
+	  <th> Duration</th>
+	  <th> Stroke Estimate 1</th>
+	  <th> Stroke Estimate 2</th>
+        <tr>
+      </thead>
+      <tbody>
+				<tr>
+					<td>{{ duration }}</td>
+					<td>{{ power }}</td>
+					<td>{{ upper }}</td>
+					</tr>
+      </tbody>
+    </table>
+    </p>
diff --git a/rowers/templates/user_analysis_select.html b/rowers/templates/user_analysis_select.html
index 853039d7..65722c5c 100644
--- a/rowers/templates/user_analysis_select.html
+++ b/rowers/templates/user_analysis_select.html
@@ -124,13 +124,13 @@
 <script>
   // script for chart options form
   $(function() {
-
+      
       // Get the form fields and hidden div
       var functionfield = $("#id_function");
       var plotfield = $("#id_plotfield").parent().parent();
       var x_param = $("#id_xparam").parent().parent();
       var y_param = $("#id_yparam").parent().parent();
-
+      
       var groupby = $("#id_groupby").parent().parent();
       var binsize = $("#id_binsize").parent().parent();
       var errorbars = $("#id_ploterrorbars").parent().parent();
@@ -139,17 +139,18 @@
       var spmmax = $("#id_spmmax").parent().parent();
       var workmin = $("#id_workmin").parent().parent();
       var workmax = $("#id_workmax").parent().parent();
-
+      
       var xaxis = $("#id_xaxis").parent().parent();
       var yaxis1 = $("#id_yaxis1").parent().parent();
       var yaxis2 = $("#id_yaxis2").parent().parent();
       var plottype = $("#id_plottype").parent().parent();
-
-			var reststrokes = $("#id_includereststrokes").parent().parent();
-			var trendline = $("#id_trendline").parent().parent();
-			var piece = $("#id_piece").parent().parent();
-			var cpfit = $("#id_cpfit").parent().parent();
-			var cpoverlay = $("#id_cpoverlay").parent().parent();
+      
+      var reststrokes = $("#id_includereststrokes").parent().parent();
+      var trendline = $("#id_trendline").parent().parent();
+      var piece = $("#id_piece").parent().parent();
+      var cpfit = $("#id_cpfit").parent().parent();
+      var crfit = $("#id_crfit").parent().parent();
+      var cpoverlay = $("#id_cpoverlay").parent().parent();
 
 
       // Hide the fields.
@@ -166,15 +167,15 @@
       yaxis1.hide();
       yaxis2.hide();
       plottype.hide();
-			// reststrokes.hide();
-			workmin.hide();
-			workmax.hide();
-			spmmin.hide();
-			spmmax.hide();
-			cpfit.hide();
-			cpoverlay.hide();
-			piece.hide();
-			trendline.hide();
+      // reststrokes.hide();
+      workmin.hide();
+      workmax.hide();
+      spmmin.hide();
+      spmmax.hide();
+      cpfit.hide();
+      cpoverlay.hide();
+      piece.hide();
+      trendline.hide();
 
       if (functionfield.val() == 'boxplot') {
 	  plotfield.show();
@@ -214,11 +215,16 @@
 		reststrokes.show();
       }
 
-			if (functionfield.val() == 'cp') {
-				cpfit.show();
-				piece.show();
-				cpoverlay.show();
-			}
+      if (functionfield.val() == 'cp') {
+	  cpfit.show();
+	  piece.show();
+	  cpoverlay.show();
+      }
+
+      if (functionfield.val() == 'cr') {
+	  crfit.show();
+	  piece.show();
+      }
 
 
       // Setup an event listener for when the state of the
@@ -241,15 +247,16 @@
 	      palette.hide();
 	      binsize.hide();
 	      errorbars.hide();
-				trendline.hide();
+	      trendline.hide();
 	      xaxis.hide();
 	      yaxis1.hide();
 	      yaxis2.hide();
 	      plottype.hide();
-				reststrokes.show();
-				cpfit.hide();
-				cpoverlay.hide();
-				piece.hide();
+	      reststrokes.show();
+	      cpfit.hide();
+	      crfit.hide();
+	      cpoverlay.hide();
+	      piece.hide();
 	  }
 	  else if (Value=='histo') {
 	      plotfield.show();
@@ -262,16 +269,17 @@
 	      groupby.hide();
 	      palette.hide();
 	      binsize.hide();
-				trendline.hide();
+	      trendline.hide();
 	      errorbars.hide();
 	      xaxis.hide();
 	      yaxis1.hide();
 	      yaxis2.hide();
 	      plottype.hide();
-				reststrokes.show();
-				cpfit.hide();
-				cpoverlay.hide();
-				piece.hide();
+	      reststrokes.show();
+	      cpfit.hide();
+	      crfit.hide();
+	      cpoverlay.hide();
+	      piece.hide();
 
 	  }
 	  else if (Value=='trendflex') {
@@ -284,17 +292,18 @@
 	      spmmin.show();
 	      spmmax.show();
 	      workmin.show();
-				trendline.hide();
+	      trendline.hide();
 	      workmax.show();
 	      plotfield.hide();
 	      xaxis.hide();
 	      yaxis1.hide();
 	      yaxis2.hide();
 	      plottype.hide();
-				reststrokes.show();
-				cpfit.hide();
-				cpoverlay.hide();
-				piece.hide();
+	      reststrokes.show();
+	      cpfit.hide();
+	      crfit.hide();
+	      cpoverlay.hide();
+	      piece.hide();
 
 	  }
 	  else if (Value=='flexall') {
@@ -305,7 +314,7 @@
 	      y_param.hide();
 	      groupby.hide();
 	      spmmin.hide();
-				trendline.show();
+	      trendline.show();
 	      spmmax.hide();
 	      workmin.hide();
 	      workmax.hide();
@@ -314,10 +323,11 @@
 	      binsize.hide();
 	      plottype.hide();
 	      errorbars.hide();
-				reststrokes.show();
-				cpfit.hide();
-				cpoverlay.hide();
-				piece.hide();
+	      reststrokes.show();
+	      cpfit.hide();
+	      crfit.hide();
+	      cpoverlay.hide();
+	      piece.hide();
 	  }
 	  else if (Value=='stats') {
 	      xaxis.hide();
@@ -331,11 +341,12 @@
 	      binsize.hide();
 	      errorbars.hide();
 	      plottype.hide();
-				trendline.hide();
-				reststrokes.show();
-				cpfit.hide();
-				cpoverlay.hide();
-				piece.hide();
+	      trendline.hide();
+	      reststrokes.show();
+	      cpfit.hide();
+	      crfit.hide();
+	      cpoverlay.hide();
+	      piece.hide();
 	  }
 	  else if (Value=='compare') {
 	      xaxis.show();
@@ -350,18 +361,19 @@
 	      workmax.hide();
 	      plotfield.hide();
 	      palette.hide();
-				trendline.hide();
+	      trendline.hide();
 	      binsize.hide();
 	      plottype.show();
 	      errorbars.hide();
-				piece.hide();
-				cpfit.hide();
-				cpoverlay.hide();
-				reststrokes.show();
+	      piece.hide();
+	      cpfit.hide();
+	      crfit.hide();
+	      cpoverlay.hide();
+	      reststrokes.show();
 
 
 	  }
-		else if (Value=='cp') {
+	  else if (Value=='cp') {
 	      plotfield.hide();
 	      spmmin.hide();
 	      spmmax.hide();
@@ -369,7 +381,7 @@
 	      workmax.hide();
 	      x_param.hide();
 	      y_param.hide();
-				trendline.hide();
+	      trendline.hide();
 	      groupby.hide();
 	      palette.hide();
 	      binsize.hide();
@@ -378,10 +390,34 @@
 	      yaxis1.hide();
 	      yaxis2.hide();
 	      plottype.hide();
-				reststrokes.hide();
-				cpfit.show();
-				cpoverlay.hide();
-				piece.show();
+	      reststrokes.hide();
+	      cpfit.show();
+	      crfit.hide();
+	      cpoverlay.hide();
+	      piece.show();
+	  }
+	  else if (Value=='cr') {
+	      plotfield.hide();
+	      spmmin.hide();
+	      spmmax.hide();
+	      workmin.hide();
+	      workmax.hide();
+	      x_param.hide();
+	      y_param.hide();
+	      trendline.hide();
+	      groupby.hide();
+	      palette.hide();
+	      binsize.hide();
+	      errorbars.hide();
+	      xaxis.hide();
+	      yaxis1.hide();
+	      yaxis2.hide();
+	      plottype.hide();
+	      reststrokes.hide();
+	      cpfit.hide();
+	      crfit.show();
+	      cpoverlay.hide();
+	      piece.show();
 	  }
       });
   });
diff --git a/rowers/views/analysisviews.py b/rowers/views/analysisviews.py
index 9a1375ff..6b97f027 100644
--- a/rowers/views/analysisviews.py
+++ b/rowers/views/analysisviews.py
@@ -294,6 +294,8 @@ def analysis_new(request,
             df = comparisondata(tw, options)
         elif function == 'cp':  # pragma: no cover
             df = cpdata(tw, options)
+        elif function == 'cr':  # pragma: no cover
+            df = crdata(tw, options)
         options['savedata'] = False
         request.session['options'] = options
         try:
@@ -661,7 +663,7 @@ def cpdata(workouts, options):
     r = u.rower
     
     
-    delta, cpvalue, avgpower, workoutnames, urls = dataprep.fetchcp_new(
+    delta, cpvalue, crvalue, avgpower, workoutnames, urls = dataprep.fetchcp_new(
         r, workouts)
 
     powerdf = pl.DataFrame({
@@ -811,6 +813,139 @@ def cpdata(workouts, options):
 
     return (script, html_content)
 
+def crdata(workouts, options):
+    start = timezone.now()
+    userid = options['userid']
+    cpfit = options['cpfit']
+    cpoverlay = options['cpoverlay']
+
+    u = User.objects.get(id=userid)
+    r = u.rower
+    
+    
+    delta, cpvalue, crvalue, avgpower, workoutnames, urls = dataprep.fetchcp_new(
+        r, workouts)
+
+    powerdf = pl.DataFrame({
+        'Delta': delta,
+        'CR': crvalue,
+        'workout': workoutnames,
+        'url': urls,
+    })
+
+    savedata = options.get('savedata',False)
+    if savedata: # pragma: no cover
+        return powerdf.to_pandas()
+
+    if powerdf.is_empty():  # pragma: no cover
+        return('', '<p>No valid data found</p>')
+
+
+    powerdf = powerdf.lazy().filter(pl.col("CR")>0)
+    powerdf = powerdf.sort(["Delta", "CR"], descending=[False, True])
+    powerdf = powerdf.unique(subset="Delta", keep="first")
+    powerdf = powerdf.fill_nan(None).drop_nulls()
+    powerdf = powerdf.collect()
+
+    rowername = r.user.first_name+" "+r.user.last_name
+
+    wcdurations = []
+    wcpower = []
+
+    if len(powerdf) != 0:
+        datefirst = pd.Series(w.date for w in workouts).min()
+        datelast = pd.Series(w.date for w in workouts).max()
+        title = 'Critical Stroke Rate chart for {name}, from {d1} to {d2}'.format(
+            name=rowername,
+            d1=datefirst,
+            d2=datelast,
+        )
+        wtype = 'water'
+        if workouts[0].workouttype in mytypes.otetypes:  # pragma: no cover
+            wtype = 'erg'
+        if workouts[0].workouttype == 'bikeerg':  # pragma: no cover
+            # for Mike
+            wtype = 'erg'
+
+
+        res = interactive_otwcrchart(powerdf, promember=True, rowername=rowername, r=r,
+                                     cpfit=cpfit, title=title, type=wtype,)
+
+        script = res[0]
+        div = res[1]
+        p1 = res[2]
+        ratio = res[3]
+    else:  # pragma: no cover
+        script = ''
+        div = '<p>No ranking pieces found.</p>'
+        p1 = [1, 1, 1, 1]
+        ratio = 1
+
+    
+
+
+    minutes = options['piece']
+    if minutes != 0:
+        # minutes = 77
+        try:
+            hourvalue, tvalue = divmod(minutes, 60)
+        except:  # pragma: no cover
+            hourvalue = 0
+            tvalue = minutes
+        # hourvalue = 1, tvalue = 17
+        try:
+            hourvalue = int(hourvalue)
+        except TypeError:  # pragma: no cover
+            hourvalue = 0
+        try:
+            minutevalue = int(tvalue)
+        except TypeError:  # pragma: no cover
+            minutevalue = 0
+
+        tvalue = int(60*(tvalue-minutevalue))
+
+        if hourvalue >= 24:  # pragma: no cover
+            hourvalue = 23
+        pieceduration = datetime.time(
+            minute=minutevalue,
+            hour=hourvalue,
+            second=tvalue,
+        )
+
+        pieceseconds = 3600.*pieceduration.hour+60. * \
+            pieceduration.minute+pieceduration.second
+        # CP model
+        pwr = p1[0]/(1+pieceseconds/p1[2])
+        pwr += p1[1]/(1+pieceseconds/p1[3])
+
+        if pwr <= 0:  # pragma: no cover
+            pwr = 50.
+
+        if not np.isnan(pwr):
+            try:
+                pwr2 = pwr*ratio
+            except:  # pragma: no cover
+                pwr2 = pwr
+
+        duration = timedeltaconv(pieceseconds)
+        power = int(pwr)
+        upper = int(pwr2)
+    else:  # pragma: no cover
+        duration = timedeltaconv(0)
+        power = 0
+        upper = 0
+
+    htmly = env.get_template('otwcr.html')
+    html_content = htmly.render({
+        'script': script,
+        'the_div': div,
+        'duration': duration,
+        'power': power,
+        'upper': upper,
+    })
+
+    return (script, html_content)
+
 
 def statsdata(workouts, options):
     #try:
@@ -1063,6 +1198,8 @@ def analysis_view_data(request, userid=0):
         script, div = comparisondata(workouts, options)
     elif function == 'cp':  # pragma: no cover
         script, div = cpdata(workouts, options)
+    elif function == 'cr':  # pragma: no cover
+        script, div = crdata(workouts, options)
     else:  # pragma: no cover
         script = ''
         div = 'Unknown analysis functions'