The phrase "sets a figure" refers to the act of establishing or determining a specific numerical value, measurement, or quantity. Some antonyms for the phrase could include "uncertain," "variable," or "ambiguous," which indicate a lack of definitiveness or clarity in value determination. Other antonyms could include "decreases," "reduces," "lowers," or "diminishes," which indicate a decrease in numerical value rather than an increase or set value. Ultimately, the antonyms for "sets a figure" would depend on the specific context and nuance of the phrase and the intended meaning within that context.