Use Trading Days v.s. Block Height for Expiration?

[0xSSoul]

The origin design of hashrate contract is using a block chain height for expiration. Beacuse the mining difficulty is relative to the the block height only, using block height makes the contract much more predictable.

In Market Protocol, the contracts are expired at physical time usually. It is possible to implement this by stopping updating the index at the from Oracle at the target block height. However, this approach requires maintaining independent indexes for contracts expired at different time, which may lead to a more difficult Oracle design.

On the other hand, in order not to affect the predictability of the index, we could make the expiration time between two BTC mining diffculty adjustments.

As a result, maybe phasical system time is better??

[0xSSoul]

I propose use the phasical system time. At a setting schema at #30

[0xSSoul]

Pyasical system time is accepted by governance meeting July 14th 2019.