how many millions of coins will be mine?
A lot less than in 2016, on the Ethereum Network, the exact quantity will depend on when the Casper-POS testing is completed and that change over occurs (as most people will know the Casper POS is a specific new idea
too address the scalability of transactions on crypto-currency networks.
However, should it not be implement in 2017, there will be significant reductions of ETH with the ongoing POW period. This will occur through an increase in difficulty and slowing of block find times.
This will start when block 3,500,000 is reached in April 2017.
As a rough guide:
Block find time will slow from 14 seconds too 25 seconds
1.4 months = 518,400 Eth per month
Block find time will slow from 25 seconds too 35 seconds
2.2 months = 370,285 Eth per month
Block find time will slow from 35 seconds too 55 seconds
3.8 months = 235,636 Eth per month
Block find time will slow from 55 seconds too 95 seconds
26 months = 136,421 Eth per month
Should the Casper-POS not be implement in 2017, but in 2018. The POW situation will finish the year producing 136,421ETH per month, as opposed to over 1,000,000ETH each month.
It should be remembered: VB has hinted in a public release post recently, that testing on Casper-POS is going well and he is hopeful of an implementation of the Casper-POS this year.
Currently, POS issuance rate is being discussed by the Ethereum community.