100:1
The year model for Johnson and Evinrude outboards is determined by the "model" number, rather than the serial number.
Up through 1979 (the latest my list goes) the year of manufacture can be determined from the model number - but you didn't include the model number. It is usually on a small plate attached to the mounting bracket.
Model number J25REDR, is a 1996, 25hp Johnson.
Johnson outboard model number J175EXARG, would be a 1994 year model.
Johnson outboard model number VJ90TLATS, is a 1993 model, 90 hp.
i have a 15hp johnson with that same model number and it is a 1992
A 4 hp Johnson outboard, model number J4REIA, is a 1991 year model.
A Johnson outboat with a model number AJ25RALETS would be a 1993
A 175 hp Johnson outboard, model number J175TXCSA, would be a 1980 year model.
Johnson model number J70ELCSA, is a 1980 year model, 70 hp outboard.
A Johnson outboard, model number J88MSLCUS, is a 1987 model, 90 hp outboard.
A Johnson outboard, model number J35BALCSM, would be a 1980 model, 35 hp engine.