What Is a First Pass Yield?

A first pass yield is a quantitative numerical value, usually presented as a percentage, that indicates the amount of product being produced related to how much is used in production. This term is typically used in reference to manufacturing processes, and it can be used for individual steps in a process or for an overall process. The value can be determined fairly easily, by taking the amount of units produced in manufacturing and dividing this number by the amount of units that went into the manufacturing process. It can include units that pass through the process more than once for quality assurance, while first time yield only considers units that come out properly.

Also called a throughput yield, a first pass yield is a percentage used to evaluate the efficiency of a manufacturing process. To determine the value for a process, someone merely needs to have the numbers indicating how many units are used to make a product and how many units are made during that process. Additional information, such as units that are initially rejected but can be used after a second pass, can also be helpful. While the actual analysis and use of manufacturing data can be quite complicated, for simplicity’s sake, it is often easiest to consider small numbers.

A simple example can be considered for a manufacturing process in which 100 units of raw materials are used to product 70 units for sale. This could indicate the amount of sugar that is processed into candy bars or the amount of raw metal needed to produce cutlery. The yield for this example can be determined simply by dividing the number of produced units, 70, by the number of material units, 100. In this case, the yield would equal 0.7, or a 70% yield.

The use of a first pass yield in considering a production or manufacturing process allows a manager to quickly evaluate the efficiency of a production process. These yield numbers can be compared from one year to the next to consider how improvements in technology or manufacturing processes have increased efficiency in raw material use. While this is similar to a first time yield, there is an important difference between the two. A first time yield only considers the units that come out of the manufacturing process ready for sale, while the first pass value can include units that are defective, but that are passed through the process again to produce a salable item.