This section is a list of style issues related to calculations in the metric documentation. The calculations must balance correctness with general readability. To balance the natural tension between those things, we allow some leeway and variability in how the calculations are expressed so long as the result isn't mathematically incorrect.
General Rules
False. Capitalized, unquoted when used to indicate a variable value.
Parentheses. No spaces between open and close parenthesis and the content. Surround phrases describing a calculation in parenthesis.
Period placement. Periods following specific quoted values should go outside quotes, for example, "1-Good".
Period usage. Most lines, including equations, will end in a period. The only real exception is bullet lists only containing brief items or specific values. When in doubt, include a period, and keep bullet lists consistent (i.e., a period on all items or no period on any item).
Quotes around values. Specific text values (e.g., enumeration code values) should be surrounded by quotes, for example, "1-Good" and "3-Bad". Numerical values (e.g., 1 or 3.5) do not need quotes, nor do general descriptive terms (e.g., green, red).
Sigma. It's okay to use a sigma "∑" in calculations, though it's not required if a phrase is more elegant. Generally, the sigma should precede a parenthetical explanation of what it's summing up, for example, "∑(Students that met the daily attendance goal)". Note that there's no space between the sigma and the parenthetical.
True. Capitalized, unquoted when used to indicate a variable value.
Variables. Capitalize X and Y when used as variables. No quotes.
Rules by Example
Note parentheses, capitalization, spacing:
- School Daily Attendance Rate = ∑(Students that met the daily attendance goal) / Total number of students enrolled.
Note parentheses around two-term numerator, capitalization:
- Daily Attendance Rate = (Total number of instructional days - Total number of student excused and unexcused absences) / Total number of instructional days.