Hashprice is what one unit of hashing is expected to earn. The Gazette states it in bitcoin's own units, as sats per TH/s per day at difficulty, and computes it from the protocol alone:
hashprice = reward per block in sats × 86,400 × 10¹² ÷ (difficulty × 2³²)
The reward per block is the subsidy plus fees. A block needs difficulty × 2³² hashes on average, and one TH/s performs 10¹² hashes a second for 86,400 seconds a day, so the formula needs no estimate of the network's hashrate and no price. Every input can be read off a node: the reward from the getblockstats call (its subsidy and totalfee fields), the difficulty from getblockheader or getdifficulty. Block 968,255 paid 313,369,555 sats at difficulty 132,757,073,449,487.52, which gives 47.48 sats per TH/s per day.
None of this is realised revenue. What a miner is actually credited also depends on luck, the pool's payout scheme and fee, stale work and uptime. Difficulty adjusts every 2,016 blocks, so the figure steps at each retarget and moves with fees in between.
The dollar form. Hashprice is often quoted in dollars per petahash per second per day (USD/PH/s/day). That is the sats figure × 1,000 (TH/s to PH/s) × a bitcoin price ÷ 100,000,000, so it carries a price assumption on top of the protocol inputs and moves with the market even when mining does not. The Data Desk does not publish it: no fetched price enters a Data Desk figure.
Treat any single hashprice figure as a definition first and a number second.