diff --git a/dashboard.py b/dashboard.py
index ef4b4b1..6996eb6 100644
--- a/dashboard.py
+++ b/dashboard.py
@@ -396,7 +396,7 @@ class TimeSeries(Widget):
         dt = (t_last - data[-5][0]) / 4
         k = math.log((t_last - data[0][0]) / dt / n + 1)
 
-        max_value = max([d[1] for d in self.lts.data])
+        max_value = max([d[3] if len(d) >= 4 else d[1] for d in self.lts.data])
         max_value = max(max_value, 0.001) # ensure positive
         if self.yscale == "log":
             try:
@@ -422,9 +422,17 @@ class TimeSeries(Widget):
         for i in range(n):
             t = data[i][0]
             v = data[i][1]
+            if len(data[i]) >= 4:
+                v_min = data[i][2]
+                v_max = data[i][3]
+            else:
+                v_min = data[i][1]
+                v_max = data[i][1]
             x = t2x(t)
             t_h = time.strftime("%Y-%m-%d %H:%M:%S", time.localtime(t))
             y = v2y(v)
+            y_min = v2y(v_min)
+            y_max = v2y(v_max)
             #print(t, t_h, x)
             v_data.append(
                     {
@@ -432,6 +440,8 @@ class TimeSeries(Widget):
                         "v": v,
                         "x": x,
                         "y": y,
+                        "y_min": y_min,
+                        "y_max": y_max,
                         "color": self.criticalcolor(v),
                     })
 
@@ -450,7 +460,8 @@ class TimeSeries(Widget):
             html += f"<line x1=0 y1={tm['y']} x2=1000 y2={tm['y']} stroke='#CCC' />"
             html += f"<text x=1005 y={tm['y']} fill='#888'>{tm['v_h']}</text>"
         for v in v_data:
-            html += f"<circle cx={v['x']} cy={v['y']} r=3 fill='{v['color']}' />"
+            html += f"<line x1={v['x']-3} x2={v['x']+3} y1={v['y']} y2={v['y']} stroke='{v['color']}' />"
+            html += f"<line x1={v['x']} x2={v['x']} y1={v['y_min']} y2={v['y_max']} stroke='{v['color']}' />"
         html += "</svg>"
         log.debug("len(html) = %s", len(html))
         return Markup(html)