First side is the amount of butter the recipe calls for, the second is the amount of olive oil to replace it with.  Ratio works out to around 3/4 the amount of butter called for as olive oil.

1 tsp – 3/4 tsp

1 T – 2 1/4 tsp

1/4 c – 3 T

1/3 c – 1/4 c

1/2 c – 1/4 c plus 2 T

3/4 c – 1/2 c

1 c – 3/4 C