I'm counting all powered up HIVE. When there is a power-down that exceed the powered up HIVE, I create a deposit with the remaining HIVE. Powering up HIVE and powering the same amount is not a tax event, only when I power down more hive then powered up, I have created a tax event. The powered down HIVE, which was not powered up before, is then a staking reward (Could be author, curation, witness or staking reward, but I few all as staking reward regarding tax).

Receiving HIVE through a withdrawal route is the same as a normal transfer.

I do not consider VESTS, as they do not have a price. Only when the get accessible by the tax payer through a power down, a tax event is created. So meaning when I receive an author reward as hive power, I only have to pay taxes, when I more power down as I have powered up.

Hope this makes sense.