Formulas: % of Stages

% of movement time
Minutes of MT / SPT (or TRT) x 100
Calculates minutes of movement time divided by sleep period time or total recording time and multiplying by 100 to get the total percentage.

% of Stage 1
Minutes of S1 / TST (or TRT or SPT) x 100
Calculates minutes in Stage 1 sleep by dividing by total sleep time or total recording time or sleep period time and multiplying by 100.

% of Stage 2
Minutes of S2 / TST (or TRT or SPT) x 100
Calculates minutes in Stage 2 sleep by dividing by total sleep time or total recording time or sleep period time and multiplying by 100.

% of Stage 3
Minutes of S3 / TST (or TRT or SPT) x 100
Calculates minutes in Stage 3 sleep by dividing by total sleep time or total recording time or sleep period time and multiplying by 100.

% of Stage REM
Minutes of REM / TST (or TRT or SPT) x 100
Calculates minutes in Stage REM sleep by dividing by total sleep time or total recording time or sleep period time and multiplying by 100.


Note:
These formulas are found in Fundamentals of Sleep Technology.  Check out the Formulas page for more.