Where can I find an Ethereum transactions per second graph over time?
etherchain.org now shows a chart of the average number of transactions per second during a given day. At the time of writing the peak was on the 6th of February 2016 with a 1.2 average transactions per second during the day.
The indicator is calculated by dividing the total number of transactions on a given day by the number of seconds in a day (86400).
There's a really neat page at Amberdata.io that displays the number of transactions per second, as well as, a lot of other useful transactions statistics.
Here's a graph taken from their website:
As you can see it shows the current and average number of transactions per second as well as the a historical view with the following timeframes:
6h 3d 7d 30d 6m 1y all.
Let me know if that's helpful! 😀