PLUNA
Fleet history
Table:
Aircraft

Years of operation

ATR 42-300

Boeing 707-320B

Boeing 727-100C

Boeing 737-200

Boeing 737-200 Advanced

Boeing 737-300

Boeing 737-800

Boeing 757-200

Boeing 767-300ER

de Havilland D.H.86B Express[50]

Douglas DC-2

Douglas DC-3

Douglas DC-8-60

McDonnell Douglas DC-10-30

1994–1997

Fokker F27-100 Friendship

Lockheed L-1011-500 Tristar

Potez 62[14]

Vickers Viscount 742D

1958–1982

Vickers Viscount 810

1975–1982

Reviewing the table information on 'PLUNA' in the 'Fleet history' section, draft a brief sentence that explains what the highlighted cells show and provide it inside the JSON object {"answer": "YOUR ANSWER"}.