# Decision record 5

# Show historical data even if response rate cannot be calculated for a year of information

## Status

Completed

## Context

After story #181231394 was completed, some data stopped being visualized.  Any school/year data where the response rate could not be calculated was no longer presented to the end user.  See the Consequences section of application decision record 3.  Story #181460465 was then created to show all data even if the response rate could not be calculated.

## Decision

During the response rate calculation, if the total possible number of students and teachers for a school and year has not yet been populated, we just return a response rate of 100.  We could return any response rate that fulfilled the sufficiency threshold (from 25 to 100 percent).  We chose to go with 100 percent.  We needed a valid response rate in order to allow the score to be calculated.  If there is insufficient data, the score does not get calculated.  When displaying the response rate we check if the total possible students/teachers is populated in the database and set the response rate to N/A if those values don't exist.

## Consequences

This is a stopgap measure and will be changed as soon as we have student and teacher data for the schools and years the surveys were administered.

It means there is an artificially set 100 percent response rate that does not represent the reality of a response rate that cannot be calculated.
