diff --git a/utils/chrgdincrement.go b/utils/chrgdincrement.go
index 089aff749..4756faadc 100644
--- a/utils/chrgdincrement.go
+++ b/utils/chrgdincrement.go
@@ -24,6 +24,6 @@ import "time"
 type ChargedIncrement struct {
 	Usage          time.Duration
 	Cost           *Decimal
-	AccountSID     string // AccountS charged information
+	AccountingID   string // Accounting charged information
 	CompressFactor int
 }
diff --git a/utils/chrgdincrement_test.go b/utils/chrgdincrement_test.go
new file mode 100644
index 000000000..509d2f828
--- /dev/null
+++ b/utils/chrgdincrement_test.go
@@ -0,0 +1,60 @@
+/*
+Real-time Online/Offline Charging System (OerS) for Telecom & ISP environments
+Copyright (C) ITsysCOM GmbH
+
+This program is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program.  If not, see <http://www.gnu.org/licenses/>
+*/
+
+package utils
+
+import (
+	"encoding/json"
+	"reflect"
+	"testing"
+	"time"
+)
+
+func TestJSONMarshalUnmarshal(t *testing.T) {
+	incrmt := &ChargedIncrement{
+		Usage:          time.Duration(1 * time.Hour),
+		Cost:           NewDecimalFromFloat64(2.13),
+		AccountingID:   "abbsjweejrmdhfr",
+		CompressFactor: 1,
+	}
+	jsn, err := json.Marshal(incrmt)
+	if err != nil {
+		t.Error(err)
+	}
+	var uIncrmnt ChargedIncrement
+	if err := json.Unmarshal(jsn, &uIncrmnt); err != nil {
+		t.Error(err)
+	}
+	if !reflect.DeepEqual(incrmt, &uIncrmnt) {
+		t.Errorf("expecting: %+v, received: %+v", incrmt, uIncrmnt)
+	}
+	incrmt = &ChargedIncrement{
+		Usage:          time.Duration(1 * time.Hour),
+		AccountingID:   "abbsjweejrmdhfr",
+		CompressFactor: 1,
+	}
+	if jsn, err = json.Marshal(incrmt); err != nil {
+		t.Error(err)
+	}
+	if err := json.Unmarshal(jsn, &uIncrmnt); err != nil {
+		t.Error(err)
+	}
+	if !reflect.DeepEqual(incrmt, &uIncrmnt) {
+		t.Errorf("expecting: %+v, received: %+v", incrmt, uIncrmnt)
+	}
+}
diff --git a/utils/decimal.go b/utils/decimal.go
index a25110761..bd64558b8 100644
--- a/utils/decimal.go
+++ b/utils/decimal.go
@@ -22,6 +22,34 @@ import (
 	"github.com/ericlagergren/decimal"
 )
 
-type Decimal struct {
-	val *decimal.Big
+func NewDecimalFromFloat64(x float64) *Decimal {
+	return &Decimal{new(decimal.Big).SetFloat64(x)}
+}
+
+func NewDecimal() *Decimal {
+	return &Decimal{new(decimal.Big)}
+}
+
+// Decimal extends the decimal.Big with additional methods
+type Decimal struct {
+	*decimal.Big
+}
+
+func (d *Decimal) Float64() (f float64) {
+	f, _ = d.Big.Float64()
+	return
+}
+
+func (d *Decimal) MarshalJSON() ([]byte, error) {
+	if d.Big == nil {
+		d.Big = new(decimal.Big)
+	}
+	return d.Big.MarshalText()
+}
+
+func (d *Decimal) UnmarshalJSON(data []byte) error {
+	if d.Big == nil {
+		d.Big = new(decimal.Big)
+	}
+	return d.Big.UnmarshalJSON(data)
 }