So then, for a 15k gallon pool, is it safe to say that an SWG for 20k gallons can be run about 100% for 3 years, an SWG for 30k gallons can be run at 50% for roughly 5-6 years, and an SWG for 45k gallons can be run at 33% for roughly around 8-9 years? I'm guessing the math doesn't work like...