If you're just looking for a quick calculation you can do in your head at 3 AM after a long night of boiling, a simple rule is this: Your average sugar maple puts out 2% sap, and it takes around 40:1 to turn that into syrup.
So if a batch of syrup takes around 80 gallons of sap per gallon of syrup, your sap is running around 1%.
That make sense?
2016: Homemade arch from old wood stove; 2 steam tray pans; 6 taps; 1.1 gal
2017: Same setup. 15 taps; 4.5 gal
2018: Same setup. Limited time. 12 taps and short season; 2.2 gal
2019: Very limited time. 7 taps and a short season; 1.8 gals
2020: New Mason 2x3 XL halfway through season; 9 taps 2 gals
2021: Same 2x3, 18 taps, 4.5 gals
2022: 23 taps, 5.9 gals
2023: 23 taps. Added AUF, 13.2 gals
2024: 17 taps
All on buckets