After acquiring a marketing lead, submit a quote and receive an order to make sales. Sales = number of inquiries x estimate rate x order rate. It is a management slip to get the numbers necessary to get the ratio.
Also, follow along so you don’t leave it in the pipeline.
By listing the sales amount and annual sales, you can see which leads contributed the most to sales (although profit is really desirable). If you can see the trend of leads that contribute to sales, such as a specific industry or company size, let’s focus on developing them.