My sap to syrup ratio last season was about 60 to 1.
In the first part of the season the sap was 2.6%, then fell off hard half way through.
Also I have a small section of 21 red maples that I tap not on vacuum and didn't give up much sap.
Maybe 15 gal all season. They are 10"-12" woods trees with minimal crowns
If you can get a small vacuum pump, it'll make a world of difference
Mike
12 x 16 Sugar house
18”x72” CDL drop flue
Homemade 4 post RO
125 taps on vacuum (Guzzler)
Smoky Lake 7” filter press