Given some of the major shifts in the Medicare payment landscape over the past few years, gaining an understanding of even the big-picture workings of the system can be a tall order. The Medicare Payment Advisory Commission (MedPAC) offers an updated resource that can help.

Now available for free download: MedPAC's latest version of "Payment Basics," a series of informational sheets that describe the need-to-know elements of 20 different Medicare payment systems. Areas covered include outpatient therapy, skilled nursing facilities, home health services, hospital acute inpatient services, and more. The newest version of the resource updates the 2015 edition.

Most information sheets provide background on how the system is organized and flowcharts for a visual representation of how that particular payment system works.

Quick facts from MedPAC Payment Basics: According to the MedPAC report on outpatient therapy, in 2016 Medicare spent $7.6 billion on outpatient therapy services, a 6% increase from 2015. Physical therapy services accounted for 72% of all spending in this area. In terms of settings, nursing facilities and physical therapy private practice clinics accounted for 71% of the spending, at 37% and 33%, respectively. Hospitals were next, at 16%.