diff --git a/Simulation/Aivika/Experiment/FinalStatsView.hs b/Simulation/Aivika/Experiment/FinalStatsView.hs
--- a/Simulation/Aivika/Experiment/FinalStatsView.hs
+++ b/Simulation/Aivika/Experiment/FinalStatsView.hs
@@ -141,7 +141,9 @@
             do xs <- sequence input
                liftIO $ withMVar lock $ \() ->
                  forM_ (zip xs values) $ \(x, values) ->
-                 modifyIORef values $ addSamplingStats x
+                 do y <- readIORef values
+                    let y' = addSamplingStats x y
+                    y' `seq` writeIORef values y'
      return $ return ()
 
 -- | Get the HTML code.     
diff --git a/Simulation/Aivika/Experiment/TimingStatsView.hs b/Simulation/Aivika/Experiment/TimingStatsView.hs
--- a/Simulation/Aivika/Experiment/TimingStatsView.hs
+++ b/Simulation/Aivika/Experiment/TimingStatsView.hs
@@ -130,7 +130,10 @@
                  handleSignal_ h $ \_ ->
                  do t <- time
                     x <- input
-                    liftIO $ modifyIORef stats $ addTimingStats t x
+                    liftIO $
+                      do y <- readIORef stats
+                         let y' = addTimingStats t x y
+                         y' `seq` writeIORef stats y'
      return $ return ()
      
 -- | Get the HTML code.     
diff --git a/aivika-experiment.cabal b/aivika-experiment.cabal
--- a/aivika-experiment.cabal
+++ b/aivika-experiment.cabal
@@ -1,5 +1,5 @@
 name:            aivika-experiment
-version:         0.2
+version:         0.2.1
 synopsis:        Simulation experiments for the Aivika library
 description:
     This package allows defining simulation experiments for the Aivika