I did some math, I love math. Using your original 40Th contact for $5200.

Maintenance cost per day = $11.20

Maintenance for one year = $4088

Best case scenario, the difficulty of BTC stays exactly where it is, you would create exactly 4 btc.

Profit at current btc value = $18112

Minus the cost of maintenance = $ 14024

Realistic scenario, difficulty increases at a normal rate, creating 3.43 Btc in one year.

Profit = $ 15601

Minus maintenance = $11513

Closer to worst case scenario, difficulty increases a bunch, giving you 3.12 BTC.

Profit = $14142

Minus maintenance = $10054

Now letâs say btc goes up to $10000 in that time, thatâs potentially $30k, or $25k after maintenance costs.

But what if you bought altcoins? You could either end up doubling your money or multiplying it by 10 or 20 times. Who knows.

Edit: Where are you guys seeing this 27% pool fee? That would make a huge difference on my calculations, obviously.