The data are calculated and presented every month in both BTC and USD pay rates in every year.
Great work with this data and charts, but I would also add one additional thing for live Bitcoin prices, maybe using some tools that were posted recently in bitcointalk forum.
This would show highest paying campaigns (I think Chipmixer is on top) in case members didn't spend any of their received coins.
For example, this tool was posted by member rasengan, using his website coinxc.com for showing current rate for Bitcoin:
1 Bitcoin is now worth

For more information check out original topic and his website:
https://bitcointalk.org/index.php?topic=5397711.0Maybe in the next year there's a new campaign want to pay higher pay rate and beat the 2018 record in USD value? we will see

I am more interested in breaking Bitcoin payment rates, with inflation USD is losing it's value all the time
