"WSDWBR Quarterbet EffStack" doubts about this stat

[QuintoHerore]

Hi friends,
Questions regarding the "WSDWBR Quarterbet EffStack" stat:
I understand this refers to instances where a player bets 75% of the pot on the river and wins at showdown.
1. Is the bet size 75% or 25%?
2. Does it apply to a continuous line (triple barrel) or a non-continuous line (checking the flop and/or turn)?
3. What does "EffStack" refer to? Does it mean it is not an All-In bet?
Many thanks.