Similarly, PCBA shorts coverage in the past was defined as the number of accessible board nodes divided by the total number of board nodes.
\text{PCBA shorts test coverage}=\frac{\#\text{ of accessible nodes} }{\#\text{ of PCBA nodes} } This node-oriented measure did not take into account how nodes may have many or few connection points to device pins, and how some of these could never (in practice) be shorted.