PPS calculation?

[itmiller]

Please help. I'm trying to understand how to calculate a realistic expected income from bitcoin mining with a pool using PPS.

Let's say I had 216 Ghash/s and I'm using BTCGuid for my pool Are the following calculations correct???

(1 / Network Difficulty * 25) - Pool Fee (7.5%)      
      
0.0000020570355057   PPS based on 12153412 difficulty
0.0000001542776629   minus pool fee   
0.0000019027578428   PPS rate (matches the pool's website)
   
I read that on average, one share will be found for every 2^32, or 4.295 billion, hashes calculated. So at 1 MHash/s, you will find a share on average every 72 minutes.      
so 3000   per minute at 216 Ghash/s    
would be 180000   per hour   
about 4320000   per day   
thus 8.219913881   revenue per day??? (doesn't seem right)   
246.5974164   per month   
2959.168997   per year   

It doesn't look right to me. When I put in 216 Ghash/s on several free calculators online I get crazy returns. What am I doing wrong?

Thank you for your help! I appreciate your time.

[mirek]

Actually there is thread about mining or investing instead:
https://bitcointalk.org/index.php?topic=56475.0
However it is complex for me. Do you have more simple excel or source for making calculations?

[itmiller]

Thanks. I'll check it out.

The calculation above is pretty simple but I don't know if I'm doing it correctly.

Have a good one!

[Epoch]

I read that on average, one share will be found for every 2^32, or 4.295 billion, hashes calculated. So at 1 MHash/s, you will find a share on average every 72 minutes.      
so 3000   per minute at 216 Ghash/s    
would be 180000   per hour   
about 4320000   per day   
thus 8.219913881   revenue per day??? (doesn't seem right)   
246.5974164   per month   
2959.168997   per year   

It doesn't look right to me. When I put in 216 Ghash/s on several free calculators online I get crazy returns. What am I doing wrong?

Thank you for your help! I appreciate your time.

Your numbers are correct. Try this one (it works): http://www.alloscomp.com/bitcoin/calculator

Just keep in mind that the 'per month' and especially the 'per year' numbers are not realistic due to the skyrocketing difficulty right now.

[mirek]

The problem with onsite calculator is that you don't know the details and I am not sure if it takes into account electricity costs and rise in mining difficulty over time.
For instance I can assume that 7950 card makes 500 MH/s, that gives me 48.98$ per month with rate below 100$ per Bitcoin (following calculator).
If no costs are taken under consideration I can get my money back for the card in 7-8 months.