A: The workers’ union is proposing to the board for a 25 percent pay rise for bus drivers.

B: In these volatile economic times, a 25 percent pay rise might seem like a pipe dream.

Note: A “pipe dream” refers to a hope, wish, or dream that is impossible to achieve or not practical. The pipe in question was something like a tobacco pipe, but it was for smoking opium. First recorded in the 1890s, this idiom alludes to an improbable and visionary hope, ideal, scheme, etc., such as one an opium smoker might have.