HPS bulbs degrade quickly and should be replaced at a minimum once a year. They degrade 20% in the first 6 months on average.
Don't know what you used for LEDs but modern LEDs like Quatum Boards and COB lighting is superior to all other horticultural lighting. HPS/MH is dead technology, within the next ten years ot less it will be gone. Gavita sold its HPS division to concentrate on LED..... that should tell you something.
Buy a bulb, clean the reflector with alcohol and get another year out of it, then take a look at upgrading. With these new LEDs efficiency is now almost double of that of HPS, with Gavita at around 35% efficient, and QBs and COBs up to 60% plus a 50,000 hr. plus life span, LED is actually cheaper than HPS when you factor on annual bulb and reflector changes.