Unless I'm missing something they only use a single 5 year window to look at the 2020 peak. I meant if you slide the window back over the past 50 years, what ot

Unless I'm missing something they only use a single 5 year window to look at the 2020 peak. I meant if you slide the window back over the past 50 years, what other peaks show up and how much larger are they then the other years in their window?