1 Onset of sleep from time the lights were turned off; this is called  sleep onset latency  and normally is less than 20 minutes. ( 2 Note that determining sleep and awake is based solely on the EEG. Patients sometimes feel they were awake when the EEG shows they were sleeping.
The direct cost margin is calculated by taking the difference between the revenue generated by the sale of goods or services and the sum of all direct costs associated with the production of those goods, divided by the total revenue.
Step 4: Determine costs as a percentage of adjusted contract revenue. If the direct margin is 40% of adjusted contract revenues, then the costs = 1-direct margin or 60%. Therefore, costs of construction (direct costs) should be 60% of the total adjusted contract revenues.