diff --git a/pdb-plotting/src/main/java/org/lucares/recommind/logs/Plotter.java b/pdb-plotting/src/main/java/org/lucares/recommind/logs/Plotter.java
index dd12c7e..6bb7c43 100644
--- a/pdb-plotting/src/main/java/org/lucares/recommind/logs/Plotter.java
+++ b/pdb-plotting/src/main/java/org/lucares/recommind/logs/Plotter.java
@@ -1,5 +1,6 @@
 package org.lucares.recommind.logs;
 
+import java.io.BufferedWriter;
 import java.io.File;
 import java.io.FileOutputStream;
 import java.io.IOException;
@@ -129,10 +130,12 @@ public class Plotter {
 		if (minDate.until(maxDate, ChronoUnit.WEEKS) > 1) {
 			formatX = "%Y-%m-%d";
 			rotateX = 0;
-		} else {
-
+		} else if (minDate.until(maxDate, ChronoUnit.SECONDS) > 10) {
 			formatX = "%Y-%m-%d %H:%M:%S";
 			rotateX = gnuplotSettings.getRotateXAxisLabel();
+		} else {
+			formatX = "%Y-%m-%d %H:%M:%.3S";
+			rotateX = gnuplotSettings.getRotateXAxisLabel();
 		}
 		formattedMinDate = minDate.format(DateTimeFormatter.ofPattern("yyyy-MM-dd'T'HH:mm:ss"));
 		formattedMaxDate = maxDate.format(DateTimeFormatter.ofPattern("yyyy-MM-dd'T'HH:mm:ss"));
@@ -214,9 +217,11 @@ public class Plotter {
 		final long fromEpochMilli = dateFrom.toInstant().toEpochMilli();
 		final long toEpochMilli = dateTo.toInstant().toEpochMilli();
 		long maxValue = 0;
+		long ignoredValues = 0;
 		final int separator = ',';
 		final int newline = '\n';
-		try (final Writer output = new OutputStreamWriter(new FileOutputStream(dataFile), StandardCharsets.US_ASCII);) {
+		final DateTimeFormatter formatter = DateTimeFormatter.ISO_LOCAL_DATE_TIME;
+		try (final Writer output = new BufferedWriter(new OutputStreamWriter(new FileOutputStream(dataFile), StandardCharsets.US_ASCII));) {
 
 			final Iterator<Entry> it = entries.iterator();
 			while (it.hasNext()) {
@@ -225,7 +230,7 @@ public class Plotter {
 				if (fromEpochMilli <= entry.getEpochMilli() && entry.getEpochMilli() <= toEpochMilli) {
 					final OffsetDateTime date = entry.getDate();
 					final String value = String.valueOf(entry.getValue());
-					final String formattedDate = date.format(DateTimeFormatter.ISO_LOCAL_DATE_TIME);
+					final String formattedDate = date.format(formatter);
 					output.write(formattedDate);
 					output.write(separator);
 					output.write(value);
@@ -233,11 +238,13 @@ public class Plotter {
 
 					count++;
 					maxValue = Math.max(maxValue, entry.getValue());
+				}else {
+					ignoredValues++;
 				}
 			}
 		}
 
-		METRICS_LOGGER.debug("wrote {} values to csv in: {}ms", count, (System.nanoTime() - start) / 1_000_000.0);
+		METRICS_LOGGER.debug("wrote {} values to csv in: {}ms (ignored {} values)", count, (System.nanoTime() - start) / 1_000_000.0, ignoredValues);
 		return new CsvSummary(count,  maxValue);
 	}
 }