To effectively analyze summative data, consider these steps (and consider how they apply to formative assessments).

Calculate the average student performance for each standard on the exam.
Analyze the questions aligned to low-performing standards and look for trends in the incorrect responses of your students. Are students selecting the same wrong answers? Is there a conceptual misconception that needs to be cleared up? Are there lagging skills students need to perform this task?
Look at individual students’ work to understand misconceptions more deeply. Are there patterns in student errors that you couldn’t see from just the data?
Select low-performing, high-priority standards for whole-class reteaches. Try and interpret the standard deeply: what would students have to know or be able to do to show they’ve mastered a standard?
Identify the students who lack the background knowledge to master that standard so you can provide extra scaffolding.
Identify other standards where smaller pockets of students haven’t shown mastery to plan small-group remediation.