diff --git a/index_calculator/_consts.py b/index_calculator/_consts.py
index f73f06c..99a2c6e 100644
--- a/index_calculator/_consts.py
+++ b/index_calculator/_consts.py
@@ -23,6 +23,7 @@
 
 _split = {
     "fx": False,
+    "3hr": "5A",
     "day": "5A",
     "week": "10A",
     "mon": "10A",
diff --git a/index_calculator/_preprocessing.py b/index_calculator/_preprocessing.py
index 4161427..3a1af7f 100644
--- a/index_calculator/_preprocessing.py
+++ b/index_calculator/_preprocessing.py
@@ -62,6 +62,7 @@ def __init__(
         time_range=None,
         crop_time_axis=True,
         check_time_axis=True,
+        convert_time_axis=True,
         **kwargs,
     ):
         if ds is None:
diff --git a/index_calculator/_processing.py b/index_calculator/_processing.py
index 55d4e2b..046eed8 100755
--- a/index_calculator/_processing.py
+++ b/index_calculator/_processing.py
@@ -213,13 +213,12 @@ def _processing(self):
             time_encoding = ds.time.encoding
             time_encoding["dtype"] = np.float64
             idx_ds.time.encoding = time_encoding
-            idx_ds = (
-                pyh.time_control(idx_ds)
-                .add_time_bounds(
-                    frequency=self.freq,
-                )
-                .ds
-            )
+            #idx_ds = (
+            #    pyh.time_control(idx_ds)
+            #    .add_time_bounds(
+            #        frequency=self.freq,
+            #    ).ds
+            # )
             self.unlimited_dims = "time"
         else:
             for dim in idx_ds[self.CIname].dims:
diff --git a/index_calculator/index_calculator.py b/index_calculator/index_calculator.py
index 3707642..9cd9d2d 100644
--- a/index_calculator/index_calculator.py
+++ b/index_calculator/index_calculator.py
@@ -61,11 +61,15 @@ def __init__(self, write=False, **kwargs):
     def _compute(self, write=False, **kwargs):
         """Compute climate index."""
         preproc_obj = preprocessing(**kwargs)
+        print('preprocessing done.')
         proc_obj = processing(preproc_obj=preproc_obj)
+        print('processing done.')
         postproc_obj = postprocessing(proc_obj=proc_obj)
+        print('postprocessing done.')
         if write is True:
             outputwriter(
                 postproc_obj=postproc_obj,
                 **kwargs,
             )
+            print('writing done.')
         return postproc_obj
diff --git a/index_calculator/tables/convert_to_frequency.json b/index_calculator/tables/convert_to_frequency.json
index 5982384..3bbeeb1 100644
--- a/index_calculator/tables/convert_to_frequency.json
+++ b/index_calculator/tables/convert_to_frequency.json
@@ -18,5 +18,25 @@
       "vas": "mean"
     },
     "freq": "D"
-  }
+  },
+"3hr": {
+    "var": {
+      "hurs": "mean",
+      "pr": "mean",
+      "prsn": "mean",
+      "rlds": "mean",
+      "rlus": "mean",
+      "rsds": "mean",
+      "rsus": "mean",
+      "sfcWind": "mean",
+      "sfcWindmax": "max",
+      "snd": "mean",
+      "tas": "mean",
+      "tasmax": "max",
+      "tasmin": "min",
+      "uas": "mean",
+      "vas": "mean"
+    },
+    "freq": "3H"
+}
 }