diff --git a/bin/hledger-simplebal b/bin/hledger-simplebal
index 22973fbac..091b16e48 100755
--- a/bin/hledger-simplebal
+++ b/bin/hledger-simplebal
@@ -3,8 +3,10 @@
 # total of `hledger balance`, optionally with arguments, as a single
 # machine-readable number.  Requires hledger 1.24 or newer.
 
+set -o pipefail
+
 VALUATION_COMMODITY="$"
-hledger bal -0 -N -X "$VALUATION_COMMODITY" --infer-market-prices -c "$VALUATION_COMMODITY 1000" --layout=bare "$@" | awk '{print $1}'
+hledger bal -0 -N -X "${VALUATION_COMMODITY}" --infer-market-prices -c "${VALUATION_COMMODITY} 1000" --layout=bare "$@" | awk '{print $1}'
 
 # Tired of complex financial reports ? This is a silly but fun and
 # occasionally useful script showing how to get "one number" semi-robustly
@@ -16,7 +18,7 @@ hledger bal -0 -N -X "$VALUATION_COMMODITY" --infer-market-prices -c "$VALUATION
 # Explanation:
 # -0 (--depth 0) hides all but top-level accounts
 # -N (--no-total) hides the totals line
-# -X COMM (--value=end,COMM) converts to a single commodity if possible (needs at least one suitable P market price declaration) 
+# -X COMM (--value=end,COMM) converts to a single commodity if possible (needs at least one suitable P market price declaration)
 # --infer-market-prices guesses P price from conversion transactions if necessary
 # -c (--commodity-style) sets a predictable number format free of thousands separators
 # --layout=bare moves the commodity symbol away from the number