diff --git a/pkg/perfdata/range.go b/pkg/perfdata/range.go
index 4e3c00d..f74ca2a 100644
--- a/pkg/perfdata/range.go
+++ b/pkg/perfdata/range.go
@@ -116,7 +116,7 @@ func ParseRange(input string) (*Range, error) {
 		case rpsInit:
 			if curRune == '@' {
 				parsed.inside = true
-				index += 1
+				index++
 			}
 			state = rpsExpectStart
 
@@ -132,7 +132,7 @@ func ParseRange(input string) (*Range, error) {
 				startOfStart = index
 				state = rpsInStart
 			}
-			index += 1
+			index++
 
 		case rpsInStart:
 			switch curRune {
@@ -146,13 +146,13 @@ func ParseRange(input string) (*Range, error) {
 			default:
 				strBuilder.WriteRune(curRune)
 			}
-			index += 1
+			index++
 
 		case rpsExpectColon:
 			switch curRune {
 			case ':':
 				state = rpsExpectEnd
-				index += 1
+				index++
 			default:
 				return nil, parseError(input, index, "expected ':'")
 			}
@@ -163,10 +163,15 @@ func ParseRange(input string) (*Range, error) {
 
 		case rpsInEnd:
 			strBuilder.WriteRune(curRune)
-			index += 1
+			index++
 		}
 	}
 
+	if state == rpsInStart {
+		// The range was a single value, so that's the upper bound.
+		parsed.start = "0"
+		state = rpsInEnd
+	}
 	if state != rpsInEnd {
 		return nil, parseError(input, index, "unexpected end of input")
 	}
diff --git a/pkg/perfdata/range_test.go b/pkg/perfdata/range_test.go
index 1313de3..8238026 100644
--- a/pkg/perfdata/range_test.go
+++ b/pkg/perfdata/range_test.go
@@ -81,12 +81,14 @@ func TestRangeParserOk(t *testing.T) {
 		{in: ":123", out: Range{start: "0", end: "123"}},
 		{in: "0:123", out: Range{start: "0", end: "123"}},
 		{in: "~:123", out: Range{start: "", end: "123"}},
+		{in: "1", out: Range{start: "0", end: "1"}},
 		{in: "@:0", out: Range{start: "0", end: "0", inside: true}},
 		{in: "@0:0", out: Range{start: "0", end: "0", inside: true}},
 		{in: "@~:0", out: Range{start: "", end: "0", inside: true}},
 		{in: "@:123", out: Range{start: "0", end: "123", inside: true}},
 		{in: "@0:123", out: Range{start: "0", end: "123", inside: true}},
 		{in: "@~:123", out: Range{start: "", end: "123", inside: true}},
+		{in: "@1", out: Range{start: "0", end: "1", inside: true}},
 	}
 
 	for _, test := range tests {
@@ -106,12 +108,10 @@ func TestRangeParserError(t *testing.T) {
 		{in: ":", errPos: 1},
 		{in: "x:1", errPos: 0},
 		{in: ":~", errPos: 1},
-		{in: "1", errPos: 1},
 		{in: "@", errPos: 1},
 		{in: "@:", errPos: 2},
 		{in: "@x:1", errPos: 1},
 		{in: "@:~", errPos: 2},
-		{in: "@1", errPos: 2},
 	}
 
 	for _, test := range tests {