Actually i'm running xf 2.1.2 with php 7.3.5
Chris might be able to make something nice to show the decline other than a before and after, but the general gist of it is that php 5.6 now represents <25% of XF2 installs and decreasing by the week and nearly 75% on 7.0 or higher.In 6 days it will be 1 year since you created this thread.
Can we have the latest updated version of the pie chart to see what has changed since then? Maybe a before/after picture? Asking out of curiosity.