There is a mistaken impression online that one can decode any and all numbers on the bottom of bottles to reveal the manufacture date and other info. That is largely true for Owens-Illinois, thanks to the good work of researcher Bill Lockhart. For other manufacturers, there is sparse knowledge. Your bottle was made by Brockway Glass in PA and yes, one can bracket the age based on the Federal Law Forbids... embossing - I created a webpage on this topic.
Finding out more about your bottle means looking for a labeled example or for advertising of the brand. Research takes time and effort but it will pay off eventually.
Do let us know if you find out more about this bottle!