The output "BID" and "OFR" columns are constructed using previous tick aggregation.
The variables "BIDSIZ" and "OFRSIZ" are aggregated by taking the sum of the respective inputs over each interval.
For the variables "SYMBOL" and "EX" aggregation doesn't really make sense,
thus the first value of the input is taken as the value for the complete output.
Column "MODE" is dropped because aggregating makes absolutely no sense.
The timestamps of the new time series are the closing times of the intervals.
Please Note:
Returned objects always contain the first observation (i.e. opening quotes,...).