diff --git a/dabo/functions/check_sell_conditions.sh b/dabo/functions/check_sell_conditions.sh
index 3ffa454..269d558 100644
--- a/dabo/functions/check_sell_conditions.sh
+++ b/dabo/functions/check_sell_conditions.sh
@@ -36,7 +36,7 @@ function check_sell_conditions {
   f_result=$(g_percentage-diff ${f_BUY_PRICE} ${f_price})
   f_BUY_PRICE_LAST_RATE_DIFF=${f_result}
   result=${f_BUY_PRICE_LAST_RATE_DIFF}
-  f_real_result=$(echo "${f_result-$FEE}" | bc)
+  f_real_result=$(echo "${f_result}-${FEE}" | bc)
 
   # store new interim result
   echo ${f_BUY_PRICE_LAST_RATE_DIFF} >>${f_TRADE_HIST_FILE_INTERIM}