Step-by-Step Programming with Base SAS 9.4

Using a Value in a Later Observation

A further requirement of Tradewinds Travel is a separate SAS data set that contains the tour that generated the most revenue. (The revenue total equals the price of the tour multiplied by the number of bookings.) One method of creating the new data set might be to follow these three steps:

1. Calculate the revenue in a DATA step.
2. Sort the data set in descending order by the revenue.
3. Use another DATA step with the OBS= data set option to write that observation.

A more efficient method compares the revenue from all observations in a single DATA step. SAS can retain a value from the current observation to use in future observations. When the processing of the DATA step reaches the next observation, ...