Based on keeping your shares for 24 hours and the number of blocks found in the last 24 hours. This is a very rough estimate.

You Haven't Found Any Shares (Yet)

As you mine, you will find shares that will increase you payout when the network finds a block. Find your address, and look at the "Avg. Time to Find Share" column. On average, it will take this long for you to find a share on this network.

What is this Share Difficulty?

Payouts are weighted based on the amount of work each share took to solve, which is proportional to the minimum share difficulty
at that time ( in this case). Your hashrate will determine how long it will take, on
average, to generate a paying share on this network.

The Avg. Time to Share column is an average estimation of how long it will take to generate one of
these shares. As there is a factor of luck involved, your actual time to generate a paying share could be much shorter, or much longer.

Network 2 has a lower minimum share difficulty than network 1 due to the lower combined hashing power here.
Network 1 has considerably more combined hashing power, and as a result, has a higher minimum share difficulty.

The current lifetime of a paying share on the VTC P2Pool network is 18 hours, or 12 found blocks, whichever occurs first.