The data in your example are VERY sparse, and it's hard to know if that's typical or not.
One very simple way to do what you want is to create a timetable, and retime it to a regular 5 minute time steps using @numel as the aggregation function. But there are 105120 5 minute intervals in one year, and if your data are typicalp, you'd be making a result that mostly had zeros in it.
