diff --git a/examples/scripts/run_health_metrics.py b/examples/scripts/run_health_metrics.py
index 8efec16..ca35570 100644
--- a/examples/scripts/run_health_metrics.py
+++ b/examples/scripts/run_health_metrics.py
@@ -89,13 +89,13 @@ def _sync_compute_metrics(device, device_id, folder):
             logger.info("Raw export failed for device %s (non-fatal)", device_id)
 
         logger.info("get_nan_ratio for device %s", device_id)
-        device.get_nan_ratio().to_csv(f"{folder}/device_{device_id}_nan_ratios.csv.gz")
+        device.get_nan_ratio().to_csv(f"{folder}/{device_id}_nan_ratios.csv.gz")
         logger.info("get_implausible_ratio for device %s", device_id)
-        device.get_implausible_ratio().to_csv(f"{folder}/device_{device_id}_implausible_ratios.csv.gz")
+        device.get_implausible_ratio().to_csv(f"{folder}/{device_id}_implausible_ratios.csv.gz")
         logger.info("get_outlier_ratio for device %s", device_id)
-        device.get_outlier_ratio().to_csv(f"{folder}/device_{device_id}_outlier_ratios.csv.gz")
+        device.get_outlier_ratio().to_csv(f"{folder}/{device_id}_outlier_ratios.csv.gz")
         logger.info("get_top_value_ratio for device %s", device_id)
-        device.get_top_value_ratio().to_csv(f"{folder}/device_{device_id}_top_value_ratios.csv.gz")
+        device.get_top_value_ratio().to_csv(f"{folder}/{device_id}_top_value_ratios.csv.gz")
     except Exception:
         logger.exception("Synchronous metric computation failed for device %s", device_id)
         return False
diff --git a/scdata/__init__.py b/scdata/__init__.py
index 483fd16..044e125 100644
--- a/scdata/__init__.py
+++ b/scdata/__init__.py
@@ -3,4 +3,4 @@
 from .test import Test
 from .models import Source, TestOptions, DeviceOptions, APIParams, FileParams, CSVParams
 
-__version__ = '1.3.2'
\ No newline at end of file
+__version__ = '1.3.3'
\ No newline at end of file
diff --git a/scdata/tools/series.py b/scdata/tools/series.py
index c55319a..5548f09 100644
--- a/scdata/tools/series.py
+++ b/scdata/tools/series.py
@@ -2,10 +2,11 @@
 
 from scdata.tools.custom_logger import logger
 
+from typing import Optional
 from pandas import Series, Timedelta
 import numpy as np
 
-def infer_sampling_rate(series: Series) -> int | None:
+def infer_sampling_rate(series: Series) -> Optional[int]:
     '''Infer the sampling rate of the given timeseries, rounded to the
     closest minute.
     '''
@@ -23,7 +24,7 @@ def infer_sampling_rate(series: Series) -> int | None:
     return integer_minutes
 
 
-def mode_ratio(series: Series, ignore_zeroes=True) -> int:
+def mode_ratio(series: Series, ignore_zeroes=True) -> float:
     '''Count the percentage of times the most common value appears in the series,
     ignoring zeroes and NaNs.'''
 
diff --git a/scdata/tools/units.py b/scdata/tools/units.py
index 0fa795e..3fcaa48 100644
--- a/scdata/tools/units.py
+++ b/scdata/tools/units.py
@@ -47,6 +47,7 @@
 unit_convertion_lut = (
     ['%rh', '%', 1, False],
     ['ºC', 'degC', 1, False],
+    ['°C', 'degC', 1, False],
     ['ppm', 'ppb', 1000, False],
     ['mg/m3', 'ug/m3', 1000, False],
     ['mgm3', 'ugm3', 1000, False],
@@ -96,6 +97,7 @@ def get_units_convf(sensor, from_units):
             logger.info(f"Converting units for {sensor}. From {from_units} to {channel_lut[channel]}")
             for unit in unit_convertion_lut:
                 # Get units
+                logger.debug(f"Is it {unit[0]} to {unit[1]}?")
                 if unit[0] == from_units and unit[1] == channel_lut[channel]:
                     factor = unit[2]
                     requires_conc = unit[3]