How many accumulations are in vol_6

The others seem to range from a few to tens of thousands. How many are in the master data? 200,000?

by my understanding it is similar to vol_1 - vol_5 and has ~7000 points. They are ground truth the final position of the oil. It is good question how to compare 200k and 7000 points especially when some of them is in the beginning of their journey.