What does “Nesting Ratio” mean?

Nesting Ratio refers to the stacking height of multiple nestable plastic pallets. In other words, how many nestable plastic pallets can be stacked to roughly equal the height of 1 standard stackable plastic pallet? For example, some nestable pallets have a 2:1 ratio while others have a 3:1 ratio. The higher the nest ratio the more nestable pallets can be stacked within a certain space.