How do I figure my Equity in Homestead

This is a little complicated but I will try and make it as simple as possible. My wife and I were married August 8 1997. We seperated July 15 2000 and are divorcing. We own a house and property she has lived on since 1966. She moved there when she was 9, with her parents. When her mother and father divorced in the late 70's she and her first husbnd bought out her mother, and lived there with her father. He died in 1985 and they inherited an undivided interest. So they owned it soley, between them. She divorced him in 1993, and made an equity settlement. In Jan 1996, she refinanced and paid him off. In august 1997 we got married. Now we are divorcing. As near as I can tell, in Jan 1996 when she refinanced, the house apraised for $110,000, and she owed about $80,000. We did refinance a second mortgage in 1998 and paid off an old one. The old one was about $5000, and the new one was $16000 Today we owe about $74,000. The house now appraise at $195,000. Values have gone up around us a lot in the past two years because of a new developement accross the road. I understand there is something called the "Schmidts Formula" that should be used. I am in Minnesota. How do I figure what I have comming and where can I find this formula. Thanks, sorry this is so long.

Jeff