Looks like 1 per year.

Part - for my record.
Part - emergency.
This was un unusual week; inasmuch as:-
There was no Wednesday, and Thursday fell on Friday.
If you can follow THAT, you are familiar with our "Gannins on".
Today, in lieu of the normal "Thursday" I was whisked off to an interesting talk on "The birds of the Eden valley".
As Jerra remarked. . . (In paraphrase) He told us a lot we already knew, but it was worth it to learn what we didn't know.
In consequence, nothing was shot; but this is one of my "reserves", inasmuch as  - when there's nothing to show, and there's a sufficient change I can bung one in for the record. = Three months growth since last shot:-
https://www.blipfoto.com/entry/2375772542582394547