You're paid whatever your Balance is... The Total Earned is irrelevant since after 60 days it starts to shrink (with Total Paid). Total Unpaid is an estimate, if you stopped mining with exactly 0.0025 you could end up with 0.0024 after everything clears the exchange in the balance and not get a pay out. Also as you keep mining you would add more to the 0.0025 and still get that payout so you could get a payout of 0.003.
So basically their is no way for you to calculate your next payout until you are paid and then your balance needs to be above 0.0025 again.