My rate usually goes between 180 and 270 due to my laptop being in use (adding hash rate), my wife playing WOW (lowering it a little), and me browsing the internet inbetween. So a good average would be 200.
Code:
Pooled mining earnings = hashes / 2^32 * B / D * (1 - f)
Pooled mining earnings per day = hashrate * 24 * 3600 / 2^32 * B / D * (1 - f)
B = current block reward
D = current mining difficulty
f = Pool fee
Pooled mining earnings per day = hashrate * 24 * 3600 / 2^32 * B / D * (1 - f)
B = current block reward
D = current mining difficulty
f = Pool fee
So, your expected earnings per day will be (at current difficulty = 2968775) and a pool fee of 2%:
200e06 * 3600*24 / 2^32 * 25 / 2968775 * (1 - 0.03) = 0.03286384 btc
There's going to be a lot of variance in this figure. First, you have a low hashrate, so the variance in difficulty 1 shares produced per day will be more than for other miners, at about +/- 3%.
More importantly, if you mine at a pool that doesn't provide PPS, you're going to have to factor in the luck of the pool which will increase the variance in payout much more significantly. In this case, I'd average the earnings over a week or so (more for small pools).
Thanks man, that really sheds some light on things.
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