So how many boffins do we have on the forum?
I can only claim to stretch to 4 decimal places. 
And I’ve just realised 6 years of retirement is starting to rot the brain. My instant recall of imperial fractions to decimal (and to mm) is starting to fade.
I guess our EU brothers won’t have a clue what I’m rabbiting on about. 
When I realised it was Pi day I immediately thought of Chicken Ham and Leek Pi. I am so disappointed
At 74 next week I am down to 3 decimal places.
As its Pi day because it’s written 3.14… then surely that’s an Americanism, so does that make it American Pi day?
I can still do 27 because that was what was on the T-shirt advertisement I saw as a kid which I chose to memorise. 
At one point I knew 100 decimal places. 
Some of the YouTube channels I follow have pi day videos. One guy in particular is know for Pi Day extravaganzas, e.g. printing out a mile long printout of one million digits of pi, getting a bunch of nerds to spend a week in a room calculating pi by hand, and even has asteroid number 314159 officially named after him.
A workmate back in the 70’s had an early scientific calculator running in his flat, calculating Pi to see how many decimal places it would get to.
He lived alone!