diff --git a/dabo/functions/get_boerse_de.sh b/dabo/functions/get_boerse_de.sh
index ff8fa24..e0fbca6 100644
--- a/dabo/functions/get_boerse_de.sh
+++ b/dabo/functions/get_boerse_de.sh
@@ -18,7 +18,18 @@ function get_boerse_de {
   else
     g_echo_warn "BOERSE_DE_CMD_OUT-${f_name}.tmp has wrong Syntax. - Not updating ${f_name} Index $(tail -n 10 BOERSE_DE_CMD_OUT-${f_name}.tmp)"
   fi
-  [ -e "BOERSE_DE_CMD_OUT-${f_name}" ] || echo 0 >BOERSE_DE_CMD_OUT-${f_name}
+  if ! [ -e "BOERSE_DE_CMD_OUT-${f_name}" ]
+  then
+    set -x
+    local f_old_value=$(tail -n 1 asset-histories/${f_name}.history.csv | cut -d, -f2)
+    if echo ${f_old_value} | egrep -q "^[0-9]*\.[0-9]+$"
+    then
+      echo ${f_old_value} >BOERSE_DE_CMD_OUT-${f_name}
+    else
+      echo 0 >BOERSE_DE_CMD_OUT-${f_name}
+    fi
+    set +x
+  fi
   echo "${f_timestamp},$(cat BOERSE_DE_CMD_OUT-${f_name})" >>asset-histories/${f_name}.history.csv
 }