If there could be some accounting way which indeed miners have; if the cost to mine a single coin would equal to the profit that I could gain, then probably there`s no point of achieving a higher profit because it is still break even. The cost of profit might not be inline with the source of profit in selling bitcoin (since income is based on trading exchanges); however, miners accounted their total income over their cost of getting a coin based on the value in the exchange (per coin). So, if the cost of mining is high = high profit; then it would be the same as with luxurious commodities out there. Though it cannot be compared to high-end commodities because bitcoin is not a product - it is an investment.

So my point, if the income is adjacent to its cost and cannot be monitored; and if we cannot control over it then mining nowadays is not advisable at all.