Before -standard & -marine, it means below
The next morning the radio alarm sounded, and before I could even open my... [DOC] [TLE] What does the term 'above/below 30 days moving average' in ... [PAR] Whether you are using the 50-day, 100-day or 200-day moving average, the 
method of ... A moving average is simply an arithmetic mean of a certain number 
of data points.