One of the advantages for employees in a group health plan is the contribution most employers make toward the cost of the health coverage premium â in many cases, employers pay one-half or more of the monthly premium for an employee.
The basic format consists of five decimal numerical digits. An extended ZIP+4 code, introduced in 1983, includes the five digits of the ZIP code, a hyphen, and four additional digits that determine a more specific location within a given ZIP code. The USPS provides a free online lookup tool for ZIP codes.
Most of the. preferred abbreviations in 1874 remained the. same for nearly the next 90 years. On July 1, 1963, the Post Office Department. implemented the five-digit ZIP Code, which was. placed after the state name in the last line of an. address. To provide room for the new code in the. address line, the Department published an initial. list of state abbreviations in the June 27, 1963,