diff --git a/mainwindow.ui b/mainwindow.ui
--- a/mainwindow.ui
+++ b/mainwindow.ui
@@ -18,7 +18,7 @@
     <item>
      <widget class="QwtPlot" name="plot" native="true">
       <property name="sizePolicy">
-       <sizepolicy hsizetype="Preferred" vsizetype="MinimumExpanding">
+       <sizepolicy hsizetype="Preferred" vsizetype="Expanding">
         <horstretch>0</horstretch>
         <verstretch>0</verstretch>
        </sizepolicy>