pensions/src/service/salary2020.service.ts

``` $ npm install --save pensions

import Service from './service';

export default class Presentages {
    subPath: string;
    constructor() {
        this.subPath = "salary";
    }
    get2020Salary(scale: string, grade: string, circular: string, salary: number, retired_date: string, increment_date: string) {
        return new Promise((resolve, reject) => {
            Service.get(this.subPath, { scale: scale, grade: grade, circular: circular, salary: salary, retired_date: retired_date, increment_date: increment_date, target: "2020" })
                .then(result => {
                    if (result == null) {
                        resolve(null)
                    }
                    resolve(result)
                })
                .catch(err => console.log("err"));
        });
    }
}