I've recently did a bit of calculations comparing Bitcoin and Paypal.
One of the most interesting thing that I found that Bitcoin transaction in average is much more expensive than Paypal transaction, 7 to 20 times now.
I think that it is very interesting, taking into account that cheap transaction is very often cited as a big benefit of blockchain technology.
To make it clear, the cost per transaction was calculated as revenue of system providers divided to number of transaction for the period of time.
For Bitcoin providers were minders, for Paypal - Paypal itself.
For the end of Q2 2017 I came to $2 for Paypal and $14 for Bitcoin. Now Bitcoin transaction is even more expensive, around $40.
Important to note that for miners I've calculated both direct transaction fee and mined new coin reward, I think that is the correct way. Even if we forget about new coins created, just transaction fee now is around $8.
More details with data sources and an infographic summary are available in my blog -
https://levashov.biz/paypal-vs-bitcoin-2017/
The question to community - do I miss something important? What other people think of it?
It's pretty well-known that things are more efficient if you can trust a centralized authority to maintain them. The point of Bitcoin is the decentralization, not efficiency in any way.