In a species of field mouse, coat color is influenced by a receptor protein. The mutant allele, $A^M$, is formed due to a 36 base-pair deletion from the wild-type allele, $A^W$. The receptor protein coded for by the mutant allele $A^M$ is 264 amino acids long. Calculate the percentage reduction in size of the protein coded for by the mutant allele $A^M$ compared with the protein coded for by the wild-type allele $A^W$. Give your answer to 3 significant figures and show your working.