"How do you think your contribution to the business can be calculated? Please make me a step by step calculation so that hiring you is actually a good decision

"How do you think your contribution to the business can be calculated? Please make me a step by step calculation so that hiring you is actually a good decision for our business" PS. we are small SAAS, hence any one's contribution can clearly be seen. (https://www.testinvite.com https://www.testinvite.com)