My question involves a marriage in the state of: Pennsylvania

For an amicable no-contest divorce in PA, how is the calculation done? I've seen two variations.

One is simple, where each couple's individual net worth at the time of marriage is calculated then added together. That sum is then subtracted from the current net worth (at time of divorce) and each spouse gets half of the difference.

A second one I've seen is there each spouse's net worth at time of marriage is calculated, then each spouse's individual net worth at the time of divorce is calculated (assuming each has some separate accounts that aren't joint) giving a net worth gain (net family property) for each spouse during the marriage. The difference in Net Family Properties is then ‘equalized’. Meaning, you owe your spouse half the difference between each party’s Net Family Property, per the above example from

Is either one correct or typical? What if some of the separate accounts are 401k or retirement ones from before the marriage but grew during the marriage, or rolled over into an individual IRA after job separation?