how does medicare calculate the number of quarters a person has contributed to medicare
If you paid Medicare taxes for less than 30 quarters, the standard Part A premium is $413. If you paid Medicare taxes for 30-39 quarters, the standard Part A premium is $227. In most cases, if you choose to buy Part A, you must also have Medicare Part B (Medical Insurance) and pay monthly premiums for both. Contact Social Security for more information about the Part A premium.