getNumericString(callback = null) {
        let result;
        if (AutoNumericHelper.isNull(this.rawValue)) {
            result = null;
        } else {
            // Always return a numeric string
            // The following statement gets rid of the trailing zeros in the decimal places since the current method does not pad decimals
            result = AutoNumericHelper.trimPaddedZerosFromDecimalPlaces(this.rawValue);
        }

        this._executeCallback(result, callback);

        return result;
    }
Return the unformatted value as a string.
This can also return `null` if `rawValue` is null.

@usage anElement.getNumericString();

@param {function|null} callback If a callback is passed, then the result is passed to it as its first argument, and the AutoNumeric object has its second

@returns {string|null}