diff --git a/README.md b/README.md
index 1be06a4..6d0f775 100644
--- a/README.md
+++ b/README.md
@@ -25,6 +25,7 @@ to any number of different targets, such as databases or MQTT.
 * [Installation and usage](#installation-and-usage)
   + [Running with Docker](#running-with-docker)
   + [Running as a systemd service](#running-as-a-systemd-service)
+* [Caveats](#caveats)
 * [Development](#development)
 * [License](#license)
 
@@ -112,6 +113,10 @@ There is a skeleton systemd service available in [systemd/eachwatt.service](syst
 project to `/opt/eachwatt`, copy the service file to `/etc/systemd/system/eachwatt.service`, modify it as necessary 
 and then start the service using `systemctl start eachwatt.service`.
 
+## Caveats
+
+* IotaWatt input sensors are always whole numbers, i.e. 2 watts. Output sensors don't have this limitation.
+
 ## Development
 
 Install dependencies:
diff --git a/src/eachwatt.ts b/src/eachwatt.ts
index edd30b3..cd080b0 100644
--- a/src/eachwatt.ts
+++ b/src/eachwatt.ts
@@ -56,14 +56,14 @@ const mainPollerFunc = async (config: Config) => {
 
   // Post-process power sensor data
   powerSensorData = powerSensorData.map((data) => {
+    // Apply optional data filters
+    if (data.circuit.sensor.filters) {
+      data = applyFilters(data.circuit.sensor.filters, data)
+    }
+
     if (data.power !== undefined) {
       // Round all numbers to one decimal point
       data.power = Number(data.power.toFixed(1))
-
-      // Apply optional data filters
-      if (data.circuit.sensor.filters) {
-        data = applyFilters(data.circuit.sensor.filters, data)
-      }
     }
 
     return data