diff --git a/CHANGELOG.md b/CHANGELOG.md
index dddb027..d857f47 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,6 @@
+## 0.1.2
+
+- Made implicit sign empty string.
 ## 0.1.1
 
 - Changed intl dependency version to ^0.17.0.
diff --git a/lib/src/sio_big_decimal_base.dart b/lib/src/sio_big_decimal_base.dart
index 70cfefc..9aa56c8 100644
--- a/lib/src/sio_big_decimal_base.dart
+++ b/lib/src/sio_big_decimal_base.dart
@@ -120,7 +120,7 @@ class BigDecimal extends Equatable {
   /// ```
   const BigDecimal.zero({
     int precision = defaultPrecision,
-  }) : this._(null, const [], null, precision);
+  }) : this._('', const [], null, precision);
 
   const BigDecimal._(
     this._sign,
@@ -129,7 +129,7 @@ class BigDecimal extends Equatable {
     this.precision,
   );
 
-  final String? _sign;
+  final String _sign;
 
   /// must be a valid `int` value. it is list of integers
   final List<int> _abs;
diff --git a/pubspec.yaml b/pubspec.yaml
index 0445af7..10559e8 100644
--- a/pubspec.yaml
+++ b/pubspec.yaml
@@ -1,6 +1,6 @@
 name: sio_big_decimal
 description: Numeric library to manipulate very big numbers keeping very high precision.
-version: 0.1.1
+version: 0.1.2
 repository: https://github.com/SimplioOfficial/sio_big_decimal
 
 environment: