The U.S. Postal Service may have its problems, but they evidently aren’t severe enough to persuade many supervisors and administrators to jump at an early retirement offer. Out of 3,594 Executive and Administrative Schedule employees eligible for the package, just 186 signed up by the Nov. 19 deadline, according to Postal Service figures provided today. The package—standard for the federal government–allows employees to retire early if they are at least 50 years old with a minimum of 20 years’ service, or any age with at least 25 years’ service. Unlike recent early retirement offers to postmasters, mail handlers and clerks,…