diff --git a/benchmarks/gabriel/difftimes.sh b/benchmarks/gabriel/difftimes.sh
index 5626baaf..3dac85e8 100755
--- a/benchmarks/gabriel/difftimes.sh
+++ b/benchmarks/gabriel/difftimes.sh
@@ -12,13 +12,23 @@ TS2="${2:--1}"
 DB="${3:-${BENCHDIR}/times.tsv}"
 
 if [ "$TS1" -lt 1000000000 ]; then
-    TS1=$(cut -f 7 "$DB" | sort -nru | tail -n +$((0 - TS1)) | head -1)
+    SORT_OPTS='-nu'
+    if [ "$TS1" -lt 0 ]; then
+        SORT_OPTS='-nru'
+        TS1=$((0 - TS1))
+    fi
+    TS1=$(cut -f 7 "$DB" | sort "$SORT_OPTS" | tail -n +$TS1 | head -1)
 fi
 if [ "$TS2" -lt 1000000000 ]; then
-    TS2=$(cut -f 7 "$DB" | sort -nru | tail -n +$((0 - TS2)) | head -1)
+    SORT_OPTS='-nu'
+    if [ "$TS2" -lt 0 ]; then
+        SORT_OPTS='-nru'
+        TS2=$((0 - TS2))
+    fi
+    TS2=$(cut -f 7 "$DB" | sort "$SORT_OPTS" | tail -n +$TS2 | head -1)
 fi
 
 join -t $'\t' \
-     <(grep $'\t'"$TS1"$'\t' "$DB" | cut -f 1-2) \
-     <(grep $'\t'"$TS2"$'\t' "$DB" | cut -f 1-2) \
-    | perl -F'\t' -ane '$g=($F[1]<=0)?0:100*($F[2]-$F[1])/$F[1]; printf STDOUT "%s\t%d\t%d\t%.2f%%\n", @F, $g'
+     <(grep $'\t'"$TS1"$'\t' "$DB" | cut -f 1-2,5) \
+     <(grep $'\t'"$TS2"$'\t' "$DB" | cut -f 1-2,5) \
+    | perl -F'\t' -ane 'sub gain{($_[0]<=0)?0:100*($_[1]-$_[0])/$_[0]} $u=gain($F[1], $F[3]); $g=gain($F[2], $F[4]); printf STDOUT "%s\t%d\t%d\t%.2f%%\t%d\t%d\t%.2f%%\n", $F[0], $F[1], $F[3], $u, $F[2], $F[4], $g'