GIA Using 21-year-old plane?

Dear Ghanaweb, the Ghana International Airlines Limited website indicates the company has acquired a Boeing 757-200 with N-number N930RD. A check on the aircraft at the website of the Federal Aviation Aministration (FAA) website (http://162.58.35.241/acdatabase/nnumsql.asp?NNumbertxt=930RD) indicated the aircraft was manufactured in 1984. This means the plane, with an Airworthiness classification as standard, is 21 years old. What do you think?