When was my over/under shotgun made?

Over/Under Shotguns: (Years of Production) / Serial Number Prefixes

Regency® (Italy) : (1967 – 1982) / R

Olympian® (Japan) : (1977 – 1981) / K-R-W

Athena® (Japan, Version I) : (1982 – 1990) / D-F-FF

Athena® III, IV, V (Japan): (1990 – 2007) / DA-DF

Orion® (Japan, Version I) : (1982 – 1990) / E-G-EE-GG

Orion® I II III (Japan) : (1990 – 2007) / EN-ER-GN-GR

Side-by-Sides Athena® SxS (Italy) : (2005 -2010) / FS

Orion® SxS (Italy) : (2005 -2011 ) / FS

Athena® D’Italia III, IV, V (Italy): (2007 – 2011) / L

Orion ® D’Italia I, II, III, SC. (Italy) : (2007 – 2011 ) / B – L

Orion® I (Turkey) : (2016-) / AU